Re: [Qgis-user] QGIS-User Digest, Vol 218, Issue 9
I've had good luck with hiding the original folder/directory containing the files I'm moving (or just moving it wholesale) starting up the QGIS project when it shows the list of files it cannot find I select one and use Browse to find that file in its new location followed by Apply Changes This generally results in it finding all the other missing files that share the same directory... I'm assuming that Browse updates a "Path" that is then automatically used to check for other missing files. Also, it **may** depend on QGIS being set to use Options - General > Project Files > Default paths: Relative rather than Absolute. I always use Relative and have not checked the effect of Absolute. Of course, the file names have to be UNchanged, but it seems to work very well when I relocate whole directories. On 4/4/24 Tony Shepherd \(FarmMaps NZ\)" wrote: I am sure I am not the first to ponder how to deal with this. I have loads, thousands likely, of project files in a series of folders and subfolders. I need to move those files and folders to a new location to enable other staff to use the project files and their associated shp files, geo packages, rasters etc. ... -- Garth Fletcher ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Apple v QGIS 3.28 LTR
Hi Alice, Hold Control key down, click on the downloaded QGIS app, and choose "Open" then give permission to run it This only has to be done the first time, thereafter MacOS remembers that you authorized that specific program and will start it without quibbling. However, if you download a new QGIS you will be required to do the Control-click followed by Open to authorize that version. You are running into Apple's security which balks, unless specifically OKed by you, programs that aren't signed by Apple or an officially authorized developer... Garth Fletcher On 2/20/24 1:44 PM, qgis-user-requ...@lists.osgeo.org wrote: Looking for some urgent help! I am desperately trying to get a QGIS project done this week so need help to get it back asap!! Was having issues with QGIS with unexpected crashes on my iMac so decided to try and do an update and install the latest long term release version from the website (3.28). However, it gives this error (attached) whenever I try and open the installed software. ?Apple cannot open QGIS-LTR because it cannot check it for malicious software This software needs to be updated Contact the developer for more information?. My IT tech support team have tried in vain to uninstall and re-install it for me, with the same results. Please let me know how I can overcome this error and get QGIS back on my iMac. ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] How to download QGIS for MacOs Ventura 13.5.2
Hi Andrea, re "/macOS High Sierra (10.13) or newer is required./" In my experience, QGIS 3.32.x does NOT fully work on macOS High Sierra (10.13) The problem is with some of the processes and the library routines they call. For example, QGIS 3.32.0 cannot be used with WBT 2.2, because of "Symbol not found: __cg_jpeg_resync_to_restart", but QGIS 3.30.3 works correctly. macOS High Sierra (10.13) is still used by many who depend on somewhat older machines. Re the rest of the wording: it suggests (to me) that the security issue begins with Catalina (10.15); however it is already present in 10.13 (and earlier). System Preferences > Privacy & Security has long offered choices of allowing Apple software only, or " Apple + signed software. So even signed software can be blocked. So the instructions should apply to all macOS whenever QGIS refuses to launch. Also, it should make clear that the QGIS app itself is what is control-clicked. New users might think it is the .dmg icon... The suggested changes seem an improvement, except for the "For Users of MacOS Catalina and above:" title. What about: *For Users of MacOS:* After installing QGIS, the first launch attempt may fail due to security protections. To enable QGIS control-click on its Icon in your Applications folder and select Open in the context menu. A confirmation dialog will display where you can give permission for QGIS to run. This only has to be done once. Garth Fletcher Message: 4 Date: Thu, 2 Nov 2023 18:34:29 +0100 From: Andrea Giudiceandrea To: qgis-user@lists.osgeo.org Subject: Re: [Qgis-user] How to download QGIS for MacOs Ventura 13.5.2 Message-ID: Content-Type: text/plain; charset=UTF-8; format=flowed Hi Garth, do you think the instructions available on qgis.org are OK or should them be improved? macOS High Sierra (10.13) or newer is required. QGIS is not yet notarized as required by macOS Catalina (10.15) security rules. On first launch, please control-click on the icon and choose Open from the context menu, after which a confirmation dialog is shown and you need to click the Open button. Please have a look at https://github.com/qgis/QGIS-Website/issues/1195 in which there is a proposal to modify the instructions on qgis.org. Best regards. Andrea ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] How to download QGIS for MacOs Ventura 13.5.2
Hello Isabel,
As a security measure Mac OS refuses to run downloaded programs unless
they are recognized ("signed") as an Apple product or an Apple
registered product.
However, if you trust the download source, you can tell Mac OS to accept
a downloaded program.
Hold the Control key down and click on the program - a menu will pop-up
in which you select "Open".
You will then be asked to confirm permission.
Alternatively, right after you tried to run the program and got the
"unable to open..." message you can use "System Preferences" and choose
"Security & Privacy" which may offer you an option to permit the program
it just refused to run.
You only have to do either once, thereafter Mac OS knows to trust that
specific program - but if you download an update you will again have to
authorize that new version.
The normal download sequence is
1) download the .dmg,
2) double click on the .dmg which should open a window showing the
QGIS app and an "Applications" folder
3) drag QGIS to "Applications" - this will copy QGIS into your main
Applications folder
4) control-click on QGIS in your Applications folder and chose "Open"
5) give permission for it to be run
Thereafter you can treat it as any other trusted program...
Cordially,
Garth Fletcher
On 11/1/23 11:41 AM, Isabel Ittig-Boo wrote:
Hi,
Thanks for your attention and help.
The « error » text is the following:
« Unable to open “QGIS” as Apple cannot verify that it does not
contain malware.
This software needs to be updated. Contact the developer to learn more.
Safari downloaded this file today at 16:14. »
« Is the error when you double-click on the download .dmg file? »* I
can open it.*
*
*
After downloading the .dmg file, I get the logo on the screen:image1.jpeg
*
*
« Or is the error when you try to run QGIS? » *Yes, I think so* (see
photo, I cannot open it).
image0.jpeg
Do you have any idea what the problem is?
Thank you.
Best regards
Isabel
Switzerland
Le 25 oct. 2023 à 23:43, Garth Fletcher a écrit :
Please provide exact text pf tje error message and when it happens.
Does the file download without errors?
Is the error when you double-click on the downloaded .dmg file?
Is the error after the .dmg file opens?
Or is the error when you try to run QGIS?
Cordially,
--
Garth Fletcher
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Re: [Qgis-user] opening .sid files in QGIS
I have routinely opened .SID color orthophoto files for several years with QGIS running on a Mac. Currently using QGIS 3.30 under Mac OS X 10.13; I started using QGIS back in the 2.14 days, ~2016. I have a vague recollection of having to load a MrSID SDK, perhaps 4 or 5 years ago. Perhaps that installation has been persistent since I haven't had to do anything MrSID related since as I updated QGIS. If indeed a MrSID is needed, it can be found at <https://www.extensis.com/support/developers> -- Garth Fletcher ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] QGIS-User Digest, Vol 211, Issue 21
I've run into a similar problem (possibly the same) - that nothing shows because the layed is panned far away from screen center. Something to do with the Project not correctly storing the canvas center coords... select one of your layers and then View >> Zoom to Layer(s) That will adjust Zoom and Pan to center and display the layer in the display... Best to select one of your layers that only contains stuff from your Area of Interest if you select some huge background layer then you will be zoomed far enough out to display the entire layer... Michael Edward McNeil wrote: ... A secondary issue, by the way, is that I apparently can't see the data after I save my QGIS project, close and re-enter the app. After re-entering QGIS the Layers pane shows all the layers, all properly check-marked for visibility, just like before, but nothing shows up in the display window ? it's totally blank white. So? I'm surviving by never (or seldom ? then reloading the data) leaving the app. But, what's going on? I'm running QGIS v. 3.32.2-Lima under MacOS 12.6.8. -- Garth Fletcher, ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Installing on MacOS
If you could upgrade to OS X 10.13 (High Sierra) then you could run QGIS 3.30. That is what I have been using extensively under OS X 10.13.6 running on my Mac mini. However, it appears that QGIS 3.32 requires at least OS X 10.14 Lester Anderson via QGIS-User wrote: Quick query. Which version of QGIS is compatible with MacOS Sierra 10.12.6 -- Garth Fletcher ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] .csv table
Burt Grabowski wrote:
?Dear all, first of all I want to quickly introduce myself. My name is
Burt and I am a student of economics in Austria. I have a special
request, because I am an absolute beginner in QGIS, but have no time
left. I am writing on my diploma thesis and my supervisor wants to
have some cards in it. I spent a whole week, but I am not able to
connect a simple .csv file with the shape file. I would probably need
10 to 15 minutes, so who would please have some time left for me for a
zoom call, so that I can create some tables for my diploma thesis? I
would like to create them over the weekend, because my deadline is
getting closer and I cannot find one description of my simple problem.
Nicolas Cadieux has replied many times via QGIS-User Digest but perhaps you did
not see his replies and offers of help.
Assuming you have a shape file containing some objects, and
you have a .csv file containing lines which should connect to those objects
You need to have (or create) a field in the .CSV file whose contents matches a
field in the shape file.
It could be simply a number, or a string. The important thing is that the
content of the field in the shape file will match the content of the field in
the .csv file.
For example if the Shape file contains a field ShpTag
and the .csv file contain a field named CsvTag of the same type
Load the .csv file as a layer using the Data Manager's Delimited text option
{note: if the 1st line in the .csv contains column names, they will be used
as field names}
You then open the shape layer dialog and use the "join" pane to
a) identify the .csv file layer
b) identify the field in the .csv file (CsvTag)
c) identify the field in the shape file (ShpTag)
Each object in the shape file will then have appended to its attributes the
.csv contents from the line in the .csv file in which the contents of ShpTag
matched the contents of CsvTag.
Very easy and very powerful.
Hope the above helps more than it confuses...
--
Garth Fletcher
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[Qgis-user] Subject: CSV Table not recognised
I'm using QGIS 3.30.2 under Mac OS X 10.13.6 (High Sierra) and .CSV files are working perfectly... Maybe check the settings in the Data Source Manager - Delimited Text to make sure it is expecting an normal CSV file. One can set it to accept a variety of other text formats... Also that you've set the appropriate degree format (DMS vs decimal) if it contains geometry. Humpphrey wrote: I uploaded a database of lat and longs to a map project the first few times it worked now the programme does not recognise the data. It accepts the table but it gives a feature count of 0. Also no labels or symbologies appear. -- Garth Fletcher ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] QGIS not installing properly
That would be an excellent improvement as there have been frequent questions about Mac OS X "refusing" to run QGIS (an other wonderful applications). There is an Apple Support doc on this topic: <https://support.apple.com/guide/mac-help/open-a-mac-app-from-an-unidentified-developer-mh40616/mac> On 2/9/23 4:18 PM, Alessandro Pasotti wrote: I am wondering if we (the QGS community) should put this information somewhere to make it easily findable. We are currently in the process of redesigning the QGIS website (which includes links to the downloads for various operating systems). -- Garth Fletcher ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] QGIS not installing properly
jessica swan wrote: I am wanting to use QGIS for a project, but it will not open on my laptop because "this device cannot scan QGIS for malware". I have a MacBook Air from 2016 - its software should be updated enough to run the QGIS system, but it seems that something is wrong. Could I please get some assistance on the issue? A good problem report should include the OS X version you are using. I'm guessing that on a 2016 Mac you may be using OS X 10.13 (High Sierra) or possibly 10.14 or 10.15. By default these, and later versions such as OS X 11, refuse to run programs that are not "officially signed", UNLESS you give them permission to do so. You only have to give permission once (for a given app); there are 2 ways: 1) control-click on the application and select Open, or 2) right after having plain clicked and gotten the refusal, go to Apple > System Preferences > Security & Privacy where you may see a message about the rejection and an offer to authorize the rejected app I always use #1. As I say, you only have to do it once. Thereafter single clicking on the app, or one of its files, will start up QGIS. By the way, while in Security & Privacy / General you will see: Allow apps downloaded from: ( ) App Store (o) App Store and indentified developers That is usually set for the 2nd choice, but might have been changed to the first Neither setting allows UNsigned apps, unless you give permission as outlined above for each UNsigned app you want to run. QGIS runs beautifully on Macs. I'm using a 2011 Mac mini with OS X 10.13 for making maps with many hundreds of layers and many many GB of rasters, including LIDAR based DEMs with 1.5 foot resolution and orthophotography with 0.5 foot resolution. Cordially, -- Garth Fletcher ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Line in QGIS I can't get rid of
Look in Edit >> Annotations I struggled for days on an unremovable polygon until someone suggested "annotations" :-) -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] RAM and processing speed requirements for QGIS (Helena Farrell)
Helena Farrell wrote: Hello, I am seeking input on whether my 7 year old Mac with 8GB RAM and a 2.7gigahertz processor is likely to perform poorly at running QGIS. Since these are like the bare minimum in terms of power, and I assume QGIS is a data-heavy program, I may need to invest in a new computer. Anyone have advice on RAM and processing speed specifications that I should look for and whether a PC be better than a Mac for running this program? I am running QGIS on a 2012 Mac Mini (2.3 GHz Intel Core i7) with 8 GB RAM running OS X 10.13.6 (High Sierra). I use multiple vector layers plus a buildings layer, DEM, areal photography (color 1 foot res) covering a 30 square mile area. Performance seems excellent. I have replaced my hard drive with SSD which may be making a significant difference. I recommend trying QGIS on your old Mac - you may be surprised... Cordially, Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] excel file with lat long
Be careful if you are using "DMS" format (42º17'35.123'') to use the right symbols. In my experience, using Mac OS X, option-zero for the degree symbol is accepted, but option-k, which also makes a degree symbol, is not. Similarly, "smart quotes", i.e., those which tilt, are rejected for minutes, as are double quotes for seconds. As long as you use the right symbols it works perfectly. Of course if you are using decimal degrees (42.123456) there is no problem. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] i have been digitizing polygons for a few days and QGIS crashed
Alexandre Neto wrote: Hi, You are missing one of the most important aspects of QGIS (and most GIS software): The data is independent of the project. The project > save action saves the project, which include what layers you have loaded, what order you gave them, their styles, and so on. When you edit vector layers, you need to use the save icon in the digitising toolbar, the one next to pencil icon that you have probably clicked to start editing. This is done layer by layer. The only time I have seen QGIS prompt the user to save an edited but not yet saved layer is when you Quit. At that moment it does seem to remind one about any unsaved layers. However, if it crashes then any unsaved new layers, or unsaved changes to pre-existing layers, are lost. The crucial step,as Alexandre says, is to save the changes in the layer by clicking on the floppy diskette icon next to the pencil... Alternatively, toggling the Pencil to turn of editing will also prompt you to save changes. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] CSV Import records missing on map
CVS import of DMS coords is touchy in my experience. The degree symbol ° fails while º works. Under Mac OS X 10.13 the first is Option-Shift-8, the second is Option-0 (opt-zero). Also, it seems to want ' for minutes and ' ' for seconds, i.e., a single ' and two separate '. It rejects a normal " double quotes, and I'm sure will reject "smart" quotes, i.e., the ones that lean in different directions. Since I figured those quirks out I have not had any problems with DMS notation. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Right of Way Center Lines (krishna Ayyala)
perhaps at: <https://gis-okdot.opendata.arcgis.com/datasets/okdot::roadways/about> click on GeoJSON download other layers at <https://gis-okdot.opendata.arcgis.com/search?groupIds=ba4c7d77c5f24b1bba7e5027176b9ab6> On 6/6/21 3:00 PM, krishna Ayyala wrote: am reposting this question.I am working on a QGIS map for which I am needing the Right of Way Center Lines. Is there a place where I can download these ROW centerlines for a few areas of the state of Oklahoma. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Multiple Layer Selection
Andrea wrote: you can copy the style of a raster layer and then apply it to two or more other raster layers at once just using the "Paste Style"command in the layers selection contextual menu: select the layers, right click, select "Paste Style. Perfect! Many thanks, Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Multiple Layer Selection
I would find being able to select mutliple layers very useful when using Layer > Paste Style to change the Style of, for example, a whole set of tiled rasters. At present it seems I have to repeatedly select a single layer, then Paste Style, then select the next... Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Do GPX files contain CRS information?
Many many thanks to Nicolas Cadieux for that research! -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Trimble GeoXT 2005 Accuracy
Nicolas Cadieux wrote: Kirk could be on the right track. You could try PPP using this site. You will need to create a user name and password. Then, you upload the Rinex file. I am 99% sure you can process point from outside of Canada. I routinely use CSRS PPP to post process RINEX files from Southern New Hampshire (43°N, 72°W). Using an iGage iG3s (L1/L2 dual frequency, GPS + GLONASS) recording at 5 second epochs in forested areas, from post processing I get 30 minute recordings, 95% error ellipses < 1 meter 10 hour recordings, 95% error ellipses < 2 cm CSRS-PPP site is <https://webapp.geod.nrcan.gc.ca/geod/tools-outils/ppp.php?locale=en> enter your email address select Static and which NAD 83 epoch you want, or ITRF Submit a RINEX file (.zip compressing the file is encouraged) they will email back a detailed report You can submit for 1 of 3 levels of post processing ultra-rapid : submit > 90 minutes after end of recording rapid: submit > 24 hours after end of recording final: submit ~ 3 weeks after end of recording Major part of corrections are in ultra-rapid, the higher levels provide further refinements. FYI: Trimble provides occupation planning aids at <https://www.gnssplanning.com/#/charts> just enter your location and date and it shows you the DOP as a function of the hour of day. Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Do GPX files contain CRS information?
On 3/5/21 3:00 PM, qgis-user-requ...@lists.osgeo.org wrote: On 05.03.21 06:02, jeremy benwell wrote: I was wondering if GPX files contain CRS information? I saved some waypoints in my garmin gps and then used GPSBabel to upload those waypoints to my computer and create a GPX file. The map datum on my gps was set to GDA 94. Does my GPX file contain the CRS that my GPS was set to when I saved the waypoints (i.e. GDA 94) and if so do I need to make sure my QGIS project CRS is set to GDA 94 also? Any help would be much appreciated thank you! The headers in .gpx files from my Garmin eTrex 20 reference <http://www.topografix.com/GPX/1/1/gpx.xsd> That file states: "GPX schema version 1.1 - For more information on GPX and this schema, visit http://www.topografix.com/gpx.asp GPX uses the following conventions: all coordinates are relative to the WGS84 datum. All measurements are in metric units." Other than that reference, my .gpx files do not contain any CRS info. I believe that the .gpx coordinates always use the WGS84 datum (EPSG:4326) and that there is no way to change that in the .gpx file. See <https://www.topografix.com/gpx.asp> for details. Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] QEP: Layer Notes
Stewart Holt brings up an important distinction between Meta Data, which belongs with the layer, and Layer Notes which would belong with the project. I agree that having both would be very valuable as each serves a different and important role in documenting a project an its data sources. I would use Meta Data to document data source and its manipulation which are important if the file is imported into a different project, while I would use Layer Notes for information about layering and such in the current project. Kudos to Nyall for his proposal! -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] move 4 concentric circles from a position to
Azzurra Lentini wrote: I must draw four different concentric circles (with different sizes and same center) in many different positions: about these positions I know the center of the circles (shape file of points). In Layer Properties > Symbology of your points shape file: For Marker you could specify an Ellipse Marker and set its size to the desired size in Map Units. You can have multiple markers, so you could have 4 of such Ellipse Markers, each with it own size. Downside is that those concentric circles will only show in the display and/or PDFs, but are not a separate shape layer of their own. Depends what you need them for. I've used a similar approach to display error bounds (95%) for GSP'ed points. There are 3 error ellipse arguments provided from CSRS-PPP for post-processed points, which are used in expressions for: data Setting Expression major axisWidth "er_maj" *2 minor axisHeight"er_min" *2 orientation Rotation "er_az"+90 Works a treat! -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] GPX data in QGIS
On Mon, 2 Nov 2020 "Fernando M. Roxo da Motta" wrote If I understand it correct, this procedure will store in attribute table (as a temporary or permanent attribute) the coordinates as they are at the time it is stored. If a point is moved through edition that value will not be updated automatically. It will be necessary to store the new value in the table with the described procedure. Yes, that is correct. After an editing session you could use Field Calculator again, this time choosing "Update existing field" instead of "Create new field" and entering the same expressions ($x, $y). Of course the better solution, if feasible, is to simply use $x and $y in your calculations instead of the newly created Lat,Long fields. $x and $y will always reflect the current location without any need for Field Calculator. I originally described the Field Calculator approach because it allowed you to see the coordinates and thus might be easier for learning. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] GPX data in QGIS.
My experience is with .gpx files generated by a Garmin eTrex-20.
When I use QGIS's Data Source Manager to open a and Add a .gxp file I
see several different layers:
Tracks
Track Points
Routes
Route Points
Waypoints
The one you want is "Track Points" because it contains all the
individual points which collectively make up the tracks. "Tracks"
only contains link(s) to the various tracks that have been recorded -
it usually only contains one item unless you have saved multiple tracks.
You may also be interested in "Waypoints" if you've recorded specific
waypoints on your GPS.
So Add the layers of interest (Track Points and maybe Waypoints)
Because a .gpx file is "input only", your first step needs to be to
to right-click on the layer, select Export > Save Features As...
This will let you save the layer in a form that can be edited. Keep
this new layer (you can remove the original .gpx layer)
The layer's Attribute Table contains fields for all sorts of attributes,
but NOT including the location (Lat,Long) data which is stored
separately.
So to be able to make your own location based calculations you want to
copy the point locations into new fields in the Attribute Table.
With the layer selected, select the Field Calculator (Abaccus icon in
toolbar)
check Create a new field
enter a name, e.g., "Latid"
set Output field type to Decimal number (real)
set Output field length to 10, Precision to 6
type "$y" in the Expression window below
{$y is the location's Y axis, i.e., its latitude}
click OK
the first time it may warn you that the layer is not in edit mode and
than proceding will turn on edit mode - this is fine
Now repeat for a 2nd field, using a different field name and expression
"Longid" and $x
Now when you open the layer's Attribute Table you will see 2 new fields
at the right which contain the point's Latid and Longid values...
Save the layer if you want to keep these additions.
On 11/1/20 2:17 PM, J. M wrote:
Hi again Garth,
Well I parked this problem and only just came back to it. I may have
missed something, but when I create the new fields you suggested in the
Track they contain no information. Is this a very advanced procedure? It
seems like something quite basic, but perhaps I've underestimated it (as
I usually do with QGIS!).
Kind regards,
Jimi.
On Fri, Sep 11, 2020 at 11:51 AM J. M <mailto:jimimc...@gmail.com>> wrote:
Hi Garth,
Thanks a lot for the very complete answer! I'll give it a go as soon
as I resolve an unrelated Ubuntu problem. I hadn't realised that GPX
data wasn't automatically visible in Properties, and that fields had
to be created.
Kind regards,
Jimi.
On Fri, Sep 11, 2020 at 4:26 AM Garth Fletcher mailto:ga...@jacqcad.com>> wrote:
On 10 Sep 2020 at 20:12, J. M mailto:jimimc...@gmail.com>> wrote:
> I can successfully import .gpx files into QGIS, and they are
visible and
> can be clustered in new groups (waypoints, tracks and routes
appear as
> independent layers). The problem I'm having is that I can't
seem to find
> any way to access the data about the routes (distance, time,
etc) which is
> clearly visible in the app I used to create the tracks
The GPX file contains a number of fields whose contents you can
see /
access in the layer's Attribute Table
right-click on layer and choose Open Attribute Table
However, these are only the extra fields in the GPX records but
NOT including the x,y coordinates (Long,Lat)
To access the later, use the Field Calculator
select the layer
click on Open Field Calculator icon (Abaccus) in the menu bar
which is next to the Open Attribute Table icon in menu, or
in Processing > GDAL > Vector Table > Field Calculator
create new fields, called Lat and Long, as decimal numbers
and enter the expression $X or $Y (see Geometry > for details)
When you click OK, the new fields will be appended and filled in
with the right values.
You can then access them in the layer's Attribute Table.
With those 2 extra fields you essentially have access to everything
that was recorded in the GPX file.
You can also use Field Calculator to add more fields and populate
them with calculation results.
As an aside, Field Calculator cannot create new fields in the GPX
file; instead it creates them as temporary virtual fields.
A better approach is to first save the data in a shape file
right-click on layer, choose Export > Save selected features
then open that file instead of the original GPX.
Field Calculator will add new fields to that format.
Cordially,
Re: [Qgis-user] Grass Processing Tools fail in QGIS LTR, PR &, Nightly Builds on MacOS
on Thu, 17 Sep 2020 12:30:4 Peter Petrik wrote: "https://qgis.org/downloads/macos/nightly2/qgis_nightly2_master_20200917_044804.dmg; I downloaded the above. On startup it displays multiple "Terminated" warnings and then crashed. OS X 10.13.6 (High Sierra) running on Mac mini (Mid 2011) Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] GPX data in QGIS.
On 10 Sep 2020 at 20:12, J. M wrote: I can successfully import .gpx files into QGIS, and they are visible and can be clustered in new groups (waypoints, tracks and routes appear as independent layers). The problem I'm having is that I can't seem to find any way to access the data about the routes (distance, time, etc) which is clearly visible in the app I used to create the tracks The GPX file contains a number of fields whose contents you can see / access in the layer's Attribute Table right-click on layer and choose Open Attribute Table However, these are only the extra fields in the GPX records but NOT including the x,y coordinates (Long,Lat) To access the later, use the Field Calculator select the layer click on Open Field Calculator icon (Abaccus) in the menu bar which is next to the Open Attribute Table icon in menu, or in Processing > GDAL > Vector Table > Field Calculator create new fields, called Lat and Long, as decimal numbers and enter the expression $X or $Y (see Geometry > for details) When you click OK, the new fields will be appended and filled in with the right values. You can then access them in the layer's Attribute Table. With those 2 extra fields you essentially have access to everything that was recorded in the GPX file. You can also use Field Calculator to add more fields and populate them with calculation results. As an aside, Field Calculator cannot create new fields in the GPX file; instead it creates them as temporary virtual fields. A better approach is to first save the data in a shape file right-click on layer, choose Export > Save selected features then open that file instead of the original GPX. Field Calculator will add new fields to that format. Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] On Wed, 9 Sep 2020 at 02:00, RMG wrote:
On Wed, 9 Sep 2020 at 02:00, RMG wrote: I would like advice on purchasing a new Mac... The Mac you describe (12,1) is a "MacBook Pro (Retina, 13-inch, Early 2015)" introduced 3/2015 and discontinued 6/2016 Geekbench 5 benchmarks for Macs can be found at <https://browser.geekbench.com/mac-benchmarks> Your Early 2015 earns a score of 763/1622 on their test set. The first number, 763, is the performance of a single core while the second number, 1622, is the performance when all cores are is use. While such tests are not the whole story, they do provide an indication of performance on an average set of tasks. Too little RAM or a slow old style (rotating) disk can greatly diminish performance. Your MacBook Pro (Retina,...) MacBook Pro (13-inch, Early 2015), 763 / 1622 More recent MacBook Pro models with 1 core benchmarks > 1000 include: MacBook Pro (13-inch Mid 2020), i7, 2.3 GHz, 4 cores 1233 / 4516 MacBook Pro (13-inch Mid 2020), i5, 2.0 GHz, 4 cores 1142 / 4238 MacBook Pro (15-inch Mid 2019), i9, 2.4 GHz, 8 cores 1115 / 6746 MacBook Pro (16-inch Late 2019), i9, 2.4 GHz, 8 cores 1110 / 6945 MacBook Pro (13-inch Mid 2019), i7, 2.8 GHz, 4 cores 1103 / 4186 MacBook Pro (15-inch Mid 2019), i9, 2.3 GHz, 8 cores 1082 / 6287 MacBook Pro (16-inch Late 2019), i9, 2.3 GHz, 8 cores 1074 / 6615 MacBook Pro (15-inch Mid 2018), i9, 2.9 GHz, 6 cores 1044 / 5052 MacBook Pro (13-inch Mid 2019), i7, 1.7 GHz, 4 cores 1032 / 3882 MacBook Pro (16-inch Late 2019), i7, 2.6 GHz, 6 cores 1022 / 5374 MacBook Pro (13-inch Mid 2018), i7, 2.7 GHz, 4 cores 1021 / 3989 MacBook Pro (15-inch Mid 2019), i7, 2.6 GHz, 6 cores 1020 / 5054 The "i5", "i7" and "i9" refer to different generations of the Intel CPU chips used. Most have SSD (Solid State Disk) rather than rotating hard disks, which make a trememdous difference, especially with software that accesses very large amounts of file data such as QGIS. Also consider the large amount of disk space needed if you use many raster files. Orthophotographs can require many GB just to cover a single town. So far my 1 TB SSD has been adequate, but my focus is on just a small area under 50 square miles, albeit with many layers of LIDAR, DEM, orthophotos, etc. For GIS use I would want a larger screen than 13", or plan on using a large external screen whenever practical. I find my 24" ViewSonic, which cost under $200, to be just large enough for comfortable GIS use. RAM is always useful and is cheap. This is an especially important consideration with MacBooks because you cannot later add more memory (MackBook Pro models after 2012). I would recommend at least 16 GB. Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] wishing for accurate lattitude/longitude from a cell, phone
A QGIS reader pointed me to a Sep 2019 US Forest Service report, <https://www.fs.fed.us/database/gps/mtdcrept/accuracy/index.htm>, which compares the accuracy of various GPS instruments. Their Garmin eTrex 30 section stated that the eTrex's accuracy was ~ 3X poorer when using GPS+GLONASS instead of GPS-only mode. This seemed rather counter-intuitive. I checked using my eTrex 20 by taking 38 measurements distributed over an 8 hour period at a precisely known location, half using GPS only and half using GPS+GLONASS modes. Canopy type probably "Light-Medium". The results indicate that GPS+GLONASS does increase the accuracy, albeit only by a modest amount. It most certainly does not decrease it! A plot of my results on a 1 meter grid, along with descriptive statistics, can be downloaded (69 KB) from: <http://www.Mason-NH.org/Specials/GARMIN±GLONASS_TESTS.pdf> Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] wishing for accurate lattitude/longitude from a cell, phone
Thanks for that very intriguing info, which I had missed.
For others interested the link mentioned is found in
Qgis-user Digest, Vol 171, Issue 50
Message: 5
From: Randal Hale
where Randy provides this link:
<https://www.fs.fed.us/database/gps/mtdcrept/accuracy/index.htm>
Which provides important comparisons by model and by canopy ("open",
"light-medium" and "heavy-closed").
The website is searchable by manufacturer/model, or you can download
the entire 750 test results in PDF or XLS format.
Very valuable comparisons.
At first I was confused by the "Position" column in both PDF and XLS
formats, until the website clarified this to being the number of
positions that were averaged together.
There is also a useful "NSSDA Standards" link.
Looking specifically at the Bad Elf GNSS Surveyor:
it is interesting to note the relatively small improvement when going
from single measurement to 60 averaged measurements. This confirms my
belief that the errors are not primarily random noise, which should
decrease almost 8 fold when 60 measurements are averaged. This is
consistent with my observation that the reported locations "wander"
slowly as the satellite geometry changes, i.e., are not random noise.
Looking at the Garmin eTrex 30 information:
Again there is negligible improvement from averaging.
The use of GLONASS does very significantly decrease the accuracy
(increases the errors), independent of whether WAAS is used.
The latter is quite surprising, very counter-intuitive, and very
intriguing!
As recommended I will compare some measurements with and without
GLONASS enabled.
On 5/31/20 3:44 PM, qgis-u...@stripfamily.net wrote:
On 5/31/2020 1:20 PM, Garth Fletcher wrote:
The eTrex was receiving both US GPS and Russian
GLONASS satellites, plus WAAS (as indicated by a "D" in the Garmin's
satellite signal bars).
earlier in this (very interesting) thread a pointer was provided to a
speadsheet that contained the results of the USFS tests of a wide range
of GPS units. One thing that was surprising was that for a number of
devices, including the eTrex30, the accuracy /decreased/ when GLONASS
was enabled in addition to GPS. You might want to repeat this experiment
without GLONASS to see if you experience the same effect.
--
Garth Fletcher
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Re: [Qgis-user] wishing for accurate lattitude/longitude from a cell, phone
I have added some data to my earlier report, both from my Garmin eTrex and from a Bad Elf Surveyor. As described earlier I established an accurately measured test location (± 2.4 cm) and taken 17 readings with my Garmin eTrex 20, distributed over a 10 hour period. The eTrex was receiving both US GPS and Russian GLONASS satellites, plus WAAS (as indicated by a "D" in the Garmin's satellite signal bars). These points were plotted on a 1 meter grid with a link provided in my earlier report to the PDF graph. That graph <http://www.Mason-NH.org/Specials/GARMIN_TESTS.pdf> (56 KB). has now been updated with more Garmin eTrex 20 data plus some data using a Bad Elf Surveyor. On the updated graph the original 17 points are plotted as blue unlabeled dots. I added another 12 pairs from the Garmin eTrex, taken at the same location at variable intervals throughout a 10 hour period on May 27. The first reading in each pair was taken (Mark Waypoint) and stored, followed by a second reading in which I told the Garmin to "average waypoint" before storing. This averaging takes from 4 to 10 minutes until a bar reaches "100% confidence", whatever that means. Note that this is not Garmin's recommended use - which is to average waypoints with at least 90 minutes between. However my immediate averaging should filter out short term "noise". These points are plotted as green (immediate) and red (averaged) dots, labeled x and xA, e.g., 1 and 1A, for the immediate and averaged points, respectively. I also added thin magenta lines linking the two dots in each pair. That data indicates a ±7 meter "wander", even in the averaged data. I also set a Bad Elf Surveyor at the same location and recorded data over a 2 hour period into a RINEX file. The estimated position returned by CSRS-PPP post processing (Rapid) is plotted as a yellow star. CSRS also reported a distressingly large error ellipse: 10.8 x 8.7 meters! While the Surveyor is recording via its Bad Elf app one can also display a "Deviation Plot" which shows the wandering of the measured location, centered over its recent average (past 15 minutes). This "wander" was observed to drift slowly within a 20' (6m) radius circle; i.e., in any 15 minute period the maximum drift seen was ±20' (up to 40'), but could have been larger over longer intervals. While the Surveyor is described as being compatible with US GPS and Russian GLONASS, it can use only one constellation at a time. Consequently the Surveyor tracks many fewer satellites than the eTrex which tracks both GPS and GLONASS. This further reduces its performance in less than the optimal "360° open sky" environments. The Surveyor, like the eTrex, is also a single-frequency receiver, thus its RINEX recordings cannot be post-processed by USGS OPUS. CSRS-PPP will process single-frequency data (includingg GPS + GLONASS), but is constrained by the limitations of single-frequency data and wandering data. My conclusions: under realistic field conditions (not all satellites visible) neither the Garmin eTrex nor the Bad Elf Surveyor can be relied upon for mapping-grade accuracy. the Surveyor's RINEX capability is of very limited use due to its single constellation and single-frequency limitations. the slow "wander" in single-frequency GPS location suggests that averaging, even if done with several widely spaced observations, is unlikely to improve accuracy. It would be necessary to average many dozens of readings evenly distributed throughout a satellite orbital period (~12 hours) in order to get a reasonable sampling capable of reducing uncertainty. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] wishing for accurate lattitude/longitude from, a cell phone
Hi Ray, Apologies for the typo - I had typed iGS3, but iG3s is the right number. iGage iG3s, now replaced by the iG4 which adds Galileo tracking but otherwise seems very similar to the iG3s. $2400 US. These track satellites from the US GPS, Russian GLONASS, Chinese BeiDou and, with the iG4, European Galileo constellations. Their sole function is to record from all the satellites they can track. They produce a RINEX format file which can be sent to a post processing service such as Canada's Geodetic Surveys' CSRS-PPP: <https://webapp.geod.nrcan.gc.ca/geod/tools-outils/ppp.php?locale=en> The longer the observation (recording) duration, the better CSRS-PPP can converge to an accurate location. In my experience in New Hampshire's heavily wooded environment, a 30 to 45 minute observation time generally gets me to better than ± 1 meter accuracy. Yesterday a 6 hour long observation in a small field surrounded by forest converged to within 1 inch. Dense forest canopy reduces the number of satellites that can be tracked. Also, some times of day are better than others in terms of the number of satellites and their geometry, see: <https://www.gnssplanning.com/#/charts> The iG3s was perfect for my specific conditions, but I think it is not optimal where many locations within a site must be accurately measured ** relative ** to each other. Such sites would be better served by differential measuring where two receivers are used. One is the "Base" which is kept in a fixed location while the other is the "Rover" which is moved from place to place. The Base constantly transmits its data to the Rover over a RF link. As long as both are fairly close (within a few kilometers of each other), both see essentially identical satellite errors which can be cancelled out to produce a very precise ** difference ** in location between Base and Rover. Note that the absolute accuracy of their positions may not be as high, but the relative accuracy can be at centimeter level. In other words, the absolute accuracy might be ± several meters, but the relative accuracy will be ± centimeters. Relative location is all that is needed for site mapping. Accurate absolute location can then be determined by carefully measuring the location of the Base, which only needs to be done once. The major advantage is speed as there is no need for long observation times at each location. There is also no need for internet or cell phone connectivity - the only requirement is that the Base be able to transmit its data to the Rover at all locations of interest. Earlier in this thread <https://emlid.com/reachrs/> was mentioned as one source of such Base/Rover systems. At $ 1600 per pair they woud be less expensive than a single iG3s or iG4 and could be much more effective. However, I do not have any personal experience with such instruments. On 5/27/20 9:11 AM, QGIS.USER wrote: Hi Garth, Thank you for some very useful data. Mine own experience in archaeology fully supports your findings. Like most things in archaeology, money is scare, time is plentiful:-) So when you talk about getting sub-metre accuracy using something called "iGS3", my interest peaked:-) However, despite a reasonably thorough Google, nothing relevant turned up. What is a "iGS3" please? Thanks in advance. Ray Carpenter Chapel Archaeology. Cordially -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] wishing for accurate lattitude/longitude from, a cell phone
I gathered some field data using my Garmin eTrex 20. It was placed in a fixed location in a small field and 17 readings were taken (using Mark Waypoint) at various intervals between 11 AM and 10 PM (EST). The Garmin generally estimated the error band at 3 to 3.6 m. The Garmin was receiving both US GPS and Russian GLONASS satellites, plus WAIS (as indicated by a "D" in the Garmin's satellite signal bars). The same location was accurately measured with a dual-freq iGS3 by recording during the first ~ 6 hours and post-processing via CSRS-PPP which resolved to a 95% probability error ellipse of 2.4 cm x 1.2 cm. The CSRS report indicates that on average 10 to 11 satellites were being tracked (range of 8 to 13). The Garmin's display indicated a similar number of satellites being tracked. The Garmin waypoints were plotted on a 1 meter grid, along with the precisely determined location. This plot can be downloaded from <http://www.Mason-NH.org/Specials/GARMIN_TESTS.pdf> (21 KB). Worst case Garmin errors are > 6 m, close to twice the Garmin's estimates - see above linked plot. I am not convinced that averaging any couple such readings can do much to increase the confidence level... My conclusion is that if precision better than ± dozens of feet is needed for a number of points (such as in an archeological dig), simple hand-held instruments such as the Garmin (or cell phones) are not suitable. Using base/rover pairs, such as discussed earlier, is a much more effective solution, albeit considerably more costly (~ 1500 USD). They have the advantage of rapidly providing precise differential measurements - which are what are all that is needed to map a site. High position accuracy can be achieved with a single dual-frequency GNSS receiver, such as the iGS3 I use, but at the cost of long duration observations at each point. In my experience an observation time of at least 30 minutes is needed (in my wooded environment) to achieve ± 1 meter, and of 1 or more hours to achieve sub-meter accuracy in absolute positional accuracy (as opposed to relative positional accuracy). -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] wishing for accurate lattitude/longitude from a cell, phone
Nicolas Cadieux wrote: ... The only way, as I see it, that GARMIN is "privatizing the geography", as you nicely put it, is by selling map to their map capable units. It would be nice to have the capability of uploading our own maps to those units. Apart from that, positions, waypoints and tracks can be uploaded and download with propitiatory and non propitiatory software. I believe QGIS had a plugin capable of doing that with multiple consumer level GPS but I have never used it. ... The plugin in question is: "GarminCustomMap Export the current map canvas to a Garmin Custom Map (.kmz-file) The GarminCustomMap plugin exports the current map canvas to a .kmz- file, which is compatible with Garmin`s Custom Maps format for handheld GPS units. ..." I used it to upload my own map with contours and property boundaries of my region into my Garmin eTrex 20 and it worked very well. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] wishing for accurate lattitude/longitude from a cell phone
The situation I was working with involved 30 points, some involving long hikes through the woods, spread around the periphery of a 36 square mile area with heavy foliage and poor or non-existent cell phone coverage. This precluded the use of any real-time reference base signals. My solution thus was using a dual frequency GNSS receiver with 30+ minute observation times and post-processing to get to 1 meter accuracy. However, if the problem had been one of accurately measuring points in a smaller area, for example an archeological site, then relative positioning would have been much more practical. This would have been done, at lower cost and higher accuracy, with a base plus rover unit pair such as those described at https://emlid.com/reachrs/. Or, if good internet connection was available throughout the site, possibly with a single rover plus connection to an external reference provider. Regarding the question about where to locate the base unit, I would guess that a location with wide clear view of the sky would be the first priority, followed by good RF paths to all rover sites for the correction signals from base to rover. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] wishing for accurate lattitude/longitude from a cell phone
I got involved in a project to locate the actual boundary monuments which delimit our town. The USGS 7.5' topographic maps appeared to be in error at some locations by several hundred feet. About 30 monument locations were involved. We are in rural NH which is mostly wooded, which results in a lot of satellite signal attenuation, i.e., fewer receivable satellites. I did a first effort using a Garmin eTrex 20 (~ $200) which received both the US GPS satellites and the Russian GLONASS satellites. Receiving both is important in our high attenuation environment because it significantly increases the number of receivable satellites. Those measurements supported my suspicions about topo errors, but had error bounds in the tens of meters - not accurate enough for my purpose. Next I used a Bad Elf Surveyor (~ $600 + Mac iPad) to record 30 minutes of data into RINEX files which were then sent to CSRS-PPP for post-processing. This somewhat reduced the error bounds, but they were still ~10 meters wide, even for some 60 minute recordings. Finally I used an iGage iGS3 receiver (~ $2400) to record US GPS and GLONASS satellites for at least 30 minutes each (up to 1 hour under heavy foliage) into RINEX files sent for post-processing to CSRS-PPP. This approach finally realized the ±1 meter with 95% probability I needed. A graph of the error ellipses for the 30 monuments as predicted by CSRS-PPP post-processing, shown on a 1 foot grid, can be seen here: <http://www.Mason-NH.org/Specials/Mon_Ellipses_Final_1_ft_grid.jpg> Note that almost all are within ± 2 feet. GPS satellites broadcast on two frequencies, L1 and L5. A key difference is that the hand-held Garmin units and the Bad Elf Surveyor only use the L1 frequency whereas the iGS3 is a dual frequency receiver (L1 and L5). One large source of errors is the variable signal propagation delays in the ionosphere, which have predictable differences between the L1 and L5 frequencies. Recording both signals allows a better estimation of, and correction for, the ionospheric delays. A word about post-processing. I use the Canadian Geodetic Survey's CSRS-PPP processing because they accept data from both US GPS and Russian GLONASS satellites whereas the US Geodetic Survey's OPUS only accepts US GPS satellite data. In our heavily wooded environment the ability to use both constellations of satellites provides a crucial boost in performance. Post-processing services continuously record L1/L5 signals from hundreds of fixed sites. This allows them to accurately model the time-changing errors in GPS signals, primarily ionospheric delays but also errors in the satellite orbits and their clocks. When RINEX data is submitted, the service can look at its contemporaneous data from fixed receivers to model the errors at the time and location of the RINEX recording and thereby apply corrections. CSRS-PPP offers 3 levels of correction: ultra-rapid (90 minutes), rapid (24 hour) and final (2 weeks). Which is applied depends on how long you wait between recording the RINEX file and submitting it for post-processing. The ultra-rapid will use the 90 minutes of data preceding the recording; the rapid will use 24 hours of data, and the final will use 2 weeks of data in calculating the corrections. More data gives better models and corrections. In my experience the differences between 24 hour and 2 week corrections are minor compared to my ±1 m target accuracy. A fixed + rover approach is the gold standard for accuracy. This technique uses 2 receivers - one fixed for the duration and the other "roving" around to the various locations to be measured. As long as the two stations are fairly close they will be affected identically by the same GPS errors which can then be cancelled out. The cancelling can be done in real-time if the fixed station broadcasts its data to the rover, or it can be done by post-processing. Of course using two receivers doubles (or more) the equipment cost.-- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Subject: Current status: multiple versions on Mac
Chris asked: ... One user however is on Mac (10.12.6 MacOS Sierra) ... Peter Petrik replied: ... if you use official installer ... However, I believe that the official installer requires Mac OS 10.13 or higher and that those of us on Mac OS 10.12 are still restricted to using the KyngChaos <https://www.kyngchaos.com/software/qgis/> installers which only go up to QGIS 3.8.3 I am stuck at Mac OS 10.12.6 (and QGIS 3.8.3) but I would be delighted if it were possible to run QGIS 3.12 !) Thanks -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] las files
Andreas Neumann recommended:
If you want to go the "free" route you'll have to use PDAL outside of
QGIS (on the command-line) and convert them to GeoTIFF files. Have a
look at the PLAS tutorials at https://pdal.io/tutorial/index.html
I concur with using PDAL - it worked very well for me for converting
50+ Lidar tiles (~ 5 GB) into a GeoTiff DEM which works with QGIS.
Under Mac OS X 10.12 (Sierra) I used PDAL in the Terminal window. i.e.,
using "command lines".
Here are my somewhat cryptic notes about the process:
first merged all the .las into all.las extracting the type 2 (ground)
and 9 (water)
CD folder containing the .las files to be merged
pdal pipeline P2.json
where file P2.json contained:
{
"pipeline":[
{
"filename":"19*.las"
},
{
"type":"filters.range",
"limits":"Classification[2:2], Classification[9:9]"
},
{
"type":"writers.las",
"filename":"all_plus.las"
}
]
}
resulted in 680 MB all_plus.las file
then converted to GeoTIFF with 6' x 6' cells
pdal pipeline Ptiff.json
where file Ptiff.json contained:
{
"pipeline":[
{
"filename":"all_plus.las"
},
{
"type":"filters.reprojection",
"out_srs":"EPSG:3614"
},
{
"type":"filters.range",
"limits":"Classification[2:2], Classification[9:9]"
},
{
"type":"writers.gdal",
"filename":"all_plus.tif",
"output_type":"min",
"resolution": 6.0,
"radius": 9.0,
"window_size":1,
"data_type":"float"
}
]
}
created 198 MB file all_plus.tif
Notes:
I extracted Class 2 (ground) and Class 9 (water) to get "surface" points
In our area the tif contained a number of "noData" pixels where no
points were found within a pixel (6' x 6' area for our case) which
were classified as Ground or Water. Using larger cells, e.g., 12x12,
reduces the number of noData cells, but does not eliminated them.
QGIS > Processing > GDAL > Raster Analysis > Fill nodata
was then used to fill in the remaining noData cells through
interpolation from adjacent areas. I used a maximum reach of 30.
I wanted to create contours. When the raw Tif DEM was used the contours
were very "busy", i.e., full of little jaggedy wiggles.
So the next step was to use
QGIS > Processing > SAGA > Raster filter > Gaussian filter
to "smooth" the DEM. Settings of 2 for SD and 5 for Radius seemed to
produce acceptable contour smoothness for 5' contours
Final step was to use
QGIS > Processing > GDAL > Raster Extraction > contour
to create the contour layer.
I hope the above helps guide you through the process
--
Garth Fletcher
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Re: [Qgis-user] Moving nodes
Amila Bajic wrote: ... I can't move the nodes, it's such an easy process, but it doesn't work for me. ... You must select the layer click on the "pencil" to enable editing (1) click on the vertex (node) tool (1b) move the cursor over the polygon edge to see the nodes click and release on the desired node (5) move the cursor, the node will follow click to set the node in the new location I think you may be missing the enabling edit step -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Can not change page setting in Printer Composer (Roberto Herrero)
Roberto Herrero wrote: ... I have changed orientation to portrait and saved the modification. However, I get no effect on the page. ... Works OK here under Mac OS X 10.12.6 In print composer, Ctrl-click on page brings up pop-up menu from which I select "Page Properties" to bring up a dialog where I can set size & orientation. This seems to be the only way to access that dialog - it doesn't appear in the normal Item Properties dialog. The settings are preserved when the layout is closed and later reopened. Tested with: QGIS version 3.4.3-Madeira Compiled against Qt 5.11.2 Compiled against GDAL/OGR 2.3.2 Compiled against GEOS 3.7.0-CAPI-1.11.0 also tested with QGIS version 3.4.1-Madeira Compiled against Qt 5.11.1 Compiled against GDAL/OGR 2.3.2 Compiled against GEOS 3.7.0-CAPI-1.11.0 Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] QGIS 3.4 macOS ...
Alex wrote: I did discuss with Larry once about buying a Mac mini and racking it so we could have a build/test machine. ... If that would solve the problem I would be happy to chip in. QGIS under Mac OS X 10.12 ... is important to me! -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] QGIS 3.4.0 on Mac OS X - separate windows can't be resized
QGIS 3.4.0 under Mac OS X 10.12.6 Separate windows, i.e., "Panels" such as "Processing Toolbox", "Log Messages", "Layers", "Results Viewer", etc., cannot be resized by dragging on their lower right corner (LRC) when they are separate windows (i.e., not part of the main canvas window). This problem is new with 3.4. The cursor does not change to a sizing cursor when placed over the LRC. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Identify features doesn't work on Qgis 3.2.2 for Mac
I tried several sequences of Project > Open different projects within same run of QGIS - Identify Feature continues to work. Each time I click on a feature the layer - Feature Attributes window appears and correctly displays. However when a single feature is selected it does not get highlighted (colored) though its values do display correctly. If I click on the background (i.e., leaving QGIS for Finder) then return to QGIS, then the selected feature does get highlighted. Also, if 2 adjacent features are selected by clicking near their boundary, then both features are highlighted and the "Identify results" window is displayed rather than the "layer xxx - Feature Attributes" window. Is the problem you are reporting the failure to highlight the selected feature? If so, the same problem exists in QGIS 3.2.1-1. On 8/31/18 5:56 AM, Jesús Lopez wrote: I try it again this morning. Sometimes, randomly, the first time you open a file, identify features works correctly, but in consecutive openings (without closing Qgis) it stops working to me. El 30 ago 2018, a las 17:14, Garth Fletcher escribió: Jesús Lopez wrote: Despite the problem with map area issue on mac, there is a new problem in 3.2.2 that neither it’s present on 3.2. The identify features option does not work correctly. If you click on any object on the map (with the layer selected) nothing appears on the identify panel. Only if you open the contextual menu (right click) you can get the info. I have seen this behavior on OS X 10.11.6 and 10.13.6, both with QGIS 3.2.2-1 and Python 3.6.6. Any idea? Identify Features seems to work here with QGIS-macOS-3.2.2-1 downloaded this morning and running under Mac OS X 10.12.6 (Sierra). About QGIS info appended. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Identify features doesn't work on Qgis 3.2.2 for Mac
Jesús Lopez wrote: Despite the problem with map area issue on mac, there is a new problem in 3.2.2 that neither it’s present on 3.2. The identify features option does not work correctly. If you click on any object on the map (with the layer selected) nothing appears on the identify panel. Only if you open the contextual menu (right click) you can get the info. I have seen this behavior on OS X 10.11.6 and 10.13.6, both with QGIS 3.2.2-1 and Python 3.6.6. Any idea? Identify Features seems to work here with QGIS-macOS-3.2.2-1 downloaded this morning and running under Mac OS X 10.12.6 (Sierra). About QGIS info appended. -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] QGIS 3.2.1 Mac Map Area Issue
A reported issue, no fix yet but a work-around, see: https://issues.qgis.org/issues/19545 https://issues.qgis.org/issues/19524 -- Garth Fletcher, ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Contour Elevation Labeling
I made a contour.shp file which contains 5' contours for my area.
I contains a field "ELEV" which holds the elevation in feet.
For the maps I currently am making I wanted:
10' contour intervals
100 intervals to use heavier lines and to be labeled.
I use the following settings in the Layer Properties dialog to achieve
the above goals
Source pane:
Provider feature filter (by using Query Builder)
"ELEV"%10 = 0 {this ignores any 5' contours, e.g., 105, 115, ...
Symbology pane:
Simple line
Stroke width
Expression: if ((ELEV % 100)=0,0.20,0.075)
{use 0.200 mm lines for 100' and 0.075 mm for all others}
Label pane:
Label with
Expression: if ((ELEV % 100)=0,ELEV,NULL)
{use ELEV if a multiple of 100, otherwise no label
Hope the above helps,
--
Garth Fletcher,
Mason, NH 03048
Andrew Davies wrote:
Hello,
I am generating contours from drone deploy & trying to add on contour
interval labels on the vector in QGIS.
My current method for attempting this is:
- layer styling
- abc
- Single Labels
- Label with...
With no elevations option.
Thank you all in advance for the help.
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[Qgis-user] Many GRASS tools in Processing are unusable (QGIS 3.0.3 on Mac OS X 10.12.6)
Many of the processing tools in GRASS, which worked with QGIS 2.18.15, are unusable in QGIS 3.0.3 under Mac OS X 10.12.6. They fail with an "ERROR: Path '//' doesn't exist" message. I reported this a week ago in report #19073, but thought a reminder here might help. QGIS is a wonderful program and I'm looking forward to being able to use 3.0.x. Cordially, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] QGIS3.0.3 under Mac OS X 10.12.6 : SAGA error messages during startup
I'm running the latest QGIS3.0.3 under Mac OS X 10.12.6. It was freshly installed using "QGIS-macOS-3.0.3-1.dmg" from qgis.org Right after starting QGIS3 I find the following Processing messages in the Log Messages panel: 2018-05-28T16:37:35 CRITICAL Could not open SAGA algorithm: RiverGridGeneration.txt 'ascii' codec can't decode byte 0xc3 in position 75: ordinal not in range(128) 2018-05-28T16:37:35 WARNING Duplicate algorithm name clusteranalysis for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name confusionmatrixpolygonsgrid for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name gwrformultiplepredictors for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name gwrforsinglepredictorgriddedmodeloutput for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name gwrforsinglepredictorlayer for provider saga 2018-05-28T16:37:35 WARNING Duplicate parameter SEARCH_POINTS_ALL registered for alg inversedistanceweightedinterpolation 2018-05-28T16:37:35 WARNING Duplicate parameter SEARCH_POINTS_MAX registered for alg inversedistanceweightedinterpolation 2018-05-28T16:37:35 WARNING Duplicate algorithm name clusteranalysis for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name difference for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name polygonidentity for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name intersect for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name polygonselfintersection for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name symmetricaldifference for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name polygonuunion for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name regressionkriging for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name simplekriging for provider saga 2018-05-28T16:37:35 WARNING Duplicate algorithm name polygonupdate for provider saga I checked the file mentioned in the first (CRITICAL) message: ~/QGIS/python/plugins/processing/algs/saga/description/RiverGridGeneration.txt It does indeed contain 0xc3 at byte 75 - as the Unicode lead-in for an 'a' with umlaut (diaeresis) mark. There are also 2 other cases later in the file for 'u' with umlaut. However, when I edited the file to replace the ä and ü with plain ASCII, this had no effect on the next QGIS3 startup - same error. Perhaps the "RiverGridGeneration.txt" data is cached somewhere? So, my 2 questions are: 1) how to fix the CRITICAL error 2) what are the implications, if any, of the WARNING messages I hope someone can help. Many thanks, -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] shift or control to toggle zoomin/zoomout
The approach I'm used to is widely used in Mac software, such as Photoshop. It allows one to dynamically navigate using the following key combinations: space bar with click & drag : pan (i.e., "hand tool") space bar + Command key with click : zoom in centered on cursor space bar + Option key with click : zoom out centered on cursor It makes it very easy to navigate within an image. In most software it also changes the cursor shape to provide feedback as to its current mode. One could use the Alt or Control keys on other systems. In QGIS I've instead defined custom keystrokes to select the 3 tools - +mag, -mag and pan - but that is less efficient as it requires the extra keystrokes. Cordially -- Garth Fletcher Mason, NH 03048 ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: http://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Can not set Shortcuts which include a Cmd key
I'm running QGIS 2.6.0-Brighton under Mac OS X 10.9.5 on a Mac Mini (late 2009) 2.26 GHz Intel Core 2 Duo with 4 GB RAM. Settings Configure Shortcuts… will not let me set a shortcut which includes a Cmd key. When I click on Change, which changes to Input, it displays Ctrl- when the Cmd key is held Alt- when the Option key is held Meta- when the Ctrl key is held. The standard Keyboard Viewer shows the correct keys - Cmd, Opt(Alt) Ctrl Seems like an issue in the keyboard interpretation... -- Garth Fletcher ___ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
