Re: [Matplotlib-users] Format date tick labels
On Thursday, October 11, 2012, Benjamin Root wrote:
On Thu, Oct 11, 2012 at 4:53 PM, Mark Lawrence
breamore...@yahoo.co.ukjavascript:_e({}, 'cvml',
'breamore...@yahoo.co.uk');
wrote:
On 11/10/2012 10:55, Damon McDougall wrote:
On Wed, Oct 10, 2012 at 5:00 PM, Benjamin Root
ben.r...@ou.edujavascript:_e({}, 'cvml', 'ben.r...@ou.edu');
wrote:
On Wed, Oct 10, 2012 at 10:55 AM, Mark Lawrence
breamore...@yahoo.co.uk javascript:_e({}, 'cvml',
'breamore...@yahoo.co.uk');
wrote:
On 10/10/2012 15:41, Mark Lawrence wrote:
On 10/10/2012 14:29, Benjamin Root wrote:
I know of a few people who have difficulties with matplotlib's
datetime
handling, but they are usually operating on the scale of
milliseconds
or
less (lightning data), in which case, one is already at the edge of
the
resolution handled by python's datetime objects. However, we would
certainly welcome any sort of examples of how matplotlib fails in
handling
seconds scale and lower plots.
Cheers!
Ben Root
I'll assume that the milliseconds above is a typo. From
http://docs.python.org/library/datetime.html class
datetime.timedelta A
duration expressing the difference between two date, time, or
datetime
instances to microsecond resolution. Still, what's a factor of 1000
amongst friends? :)
http://www.python.org/dev/peps/pep-0418/ has been implemented in
Python
3.3 and talks about clocks with nanosecond resolutions. I've flagged
it
up here just in case people weren't aware.
Ah, you are right, I meant microseconds.
With apologies to Spaceballs:
Prepare to go to microsecond resolution!
No, no, microsecond resolution is too slow
Microsecond resolution is too slow?
Yes, too slow. We must use nanosecond resolution!
Prep-- Prepare Python, for nanosecond resolution!
Cheers!
Ben Root
Am I missing something here? Are seconds just floats internally? A
delta of 1e-6 is nothing (pardon the pun). A delta of 1e-9 is the
*least* I'd expect. Maybe even 1e-12. Perhaps the python interpreter
doesn't do any denormalising
http://stackoverflow.com/questions/9314534/why-does-changing-0-1f-to-0-slow-down-performance-by-10x
when encountered with deltas very close to zero...
What percentage of computer users wants a delta of 1e-12? I suspect
that the vast majority of users couldn't care two hoots about miniscule
time deltas in a world where changing time zones can cause chaos. Where
some applications cannot handle years before 1970, or 1904, or 1900 or
whatever. Or they can't go too far forward, 2036 I think but don't
quote me. Where people like myself had to put a huge amount of effort
into changing code so that applications would carry on working when the
date flipped over from 31st December 1999 to 1st January 2000. If
things were that simple why is matplotlib using third party modules like
dateutil and pytz? Why doesn't the batteries included Python already
provide this functionality?
Preach on, my brother! Preach on!
[psst -- you are facing the choir...]
Cheers!
Ben Root
Clearly I have misunderstood something and hit a nerve. Apologies.
--
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http://www.damon-is-a-geek.com
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University of Warwick
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West Midlands
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United Kingdom
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[Matplotlib-users] color pallette suggestions wanted
Hi, I have some data I want to plot using pcolormesh. It's 2d climatological data, see the attached plot. My data is in a range from -7 to +0.6. I want to be 0.0 to be clearly visible, while at the same time, the color range should show the full dynamic of the values. I played with the bwr and seismic color maps, centering on zero, so that white is 0.0. However, I'm not too happy with the dynamic range I get in the negative. Any suggestions are very welcome ... Cheers, Andreas.attachment: example.png-- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] x-label location not at xtick location?
Hi,
another question. Given the plot from my last email (I attached the code
to this one as well), I would like to have the x-labels (J, F, ...)
not at the location of the xticks, but centered in between to xticks. I
would then move the xticks so that they form the bins to the data chunks,
and the labels should be where the current xticks are.
Any suggestions are again extremely welcome :)
Cheers, Andreas.from numpy import arange, linspace, where, searchsorted, zeros, nan, loadtxt, asarray, random
from numpy.ma import masked_invalid
import matplotlib.pyplot as plt
data = random.randn(12,72)
nxbin, nybin = data.shape
xbin = linspace(0, 12, nxbin + 1)
ybin = linspace(-90, 90, nybin + 1)
pdata = masked_invalid(data)
fig = plt.figure()
spl = fig.add_subplot(111)
cmap = mpl.cm.seismic
cmap.set_bad('#cc', 1.)
pl = spl.pcolormesh(xbin, ybin, pdata.T,
cmap=cmap, edgecolors='None',
vmin=-7,vmax=7,
)
spl.axis([0., 12., ybin.min(), ybin.max()])
spl.set_xticks(xbin[1:]-.5)
spl.set_xticklabels(['J','F','M','A','M','J','J','A','S','O','N','D'],
size='large')
spl.set_xlim([0.,12.])
spl.set_xlabel(u'Month', size='x-large', fontname='Arial')
spl.set_ylabel(u'Latitude [°]', size='x-large', fontname='Arial')
spl.set_yticks(linspace(-90., 90., 7))
spl.set_yticklabels(arange(-90,91,30), size='large', fontname='Arial')
cb = plt.colorbar(mappable=pl, orientation='horizontal',
fraction=0.075, aspect=50, pad=.15)
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[Matplotlib-users] xlabels on top, ylabels on right
Hi, me again :) I'm looking for a way to have the xlabels on the top (instead of bottom), and the ylabels on the right (instead of left). I guess I could do something with twinx / twiny and just not use the left/bottom axis, but I'm sure there is some more elegant way ... Cheers, Andreas. -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] xlabels on top, ylabels on right
Hi, me again :) I'm looking for a way to have the xlabels on the top (instead of bottom), and the ylabels on the right (instead of left). I guess I could do something with twinx / twiny and just not use the left/bottom axis, but I'm sure there is some more elegant way ... I need to correct myself: I want the xticklabels / yticklabels to be on top/right. -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Accessing WMS and ESRI REST services in Matplotlib
WMS services are required to respond to GetCapabiltiies request, reporting what layers, styles, times, elevations, and projections they have available. So for example, using the Unidata WMS example below, if we do: http://motherlode.ucar.edu:8080/thredds/wms/fmrc/NCEP/NAM/CONUS_12km/NCEP-NAM-CONUS_12km-noaaport_best.ncd?service=WMSrequest=GetCapabilities we can see from the XML response that the Coordinate Reference Systems supported are: CRSEPSG:4326/CRS CRSCRS:84/CRS CRSEPSG:41001/CRS CRSEPSG:3857/CRS CRSEPSG:27700/CRS CRSEPSG:3408/CRS CRSEPSG:3409/CRS CRSEPSG:32661/CRS CRSEPSG:32761/CRS And for this server, the supported response types are: Formatimage/jpeg/Format Formatimage/png/Format Formatapplication/vnd.google-earth.kmz/Format Formatimage/gif/Format So I guess one way to proceed if you wanted to use WMS in Matplotlib and avoid reprojection in python would be to: 1. do the WMS GetCapabilities request to find the available supported Coordinate Reference Systems (which will vary with WMS server) 2. setup Basemap to use one of these CRS 3. use the bounding box of your current axis (in projection units) as part of a GetMap request to the WMS. -Rich On Thu, Oct 11, 2012 at 12:16 AM, klo uo klo...@gmail.com wrote: I guess that's it? warpimage() as it is now, checks if passed image is url, so we can add additional check if image is url, with urlparse to deduce image coordinates and projection if present, then overlay it over already created Basemap object. -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Dr. Richard P. Signell (508) 457-2229 USGS, 384 Woods Hole Rd. Woods Hole, MA 02543-1598 -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] xlabels on top, ylabels on right
On Fri, Oct 12, 2012 at 6:12 AM, Andreas Hilboll li...@hilboll.de wrote: Hi, me again :) I'm looking for a way to have the xlabels on the top (instead of bottom), and the ylabels on the right (instead of left). I guess I could do something with twinx / twiny and just not use the left/bottom axis, but I'm sure there is some more elegant way ... I need to correct myself: I want the xticklabels / yticklabels to be on top/right. I believe you are looking for tick_params(): http://matplotlib.org/api/axes_api.html?highlight=tick_param#matplotlib.axes.Axes.tick_params ax.tick_params(axis='x', labelbottom=False, labeltop=True) ax.tick_params(axis='y', labelleft=False, labelright=True) Cheers! Ben Root -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] dpi
Jae-Joon Lee lee.j.joon-re5jqeeqqe8avxtiumw...@public.gmane.org writes: On Fri, Oct 12, 2012 at 3:39 AM, Nikolaus Rath nikolaus-bth8mxji...@public.gmane.org wrote: matplotlib actually rescales the raw imshow data when saving to a vector format? Why is that? I think it should embed the bitmap with full resolution in the vector file and rely on the consumer of the vector file to scale it to whatever resolution is supported by the display device. imshow supports interpolation and that's why rasterization comes in. If you turn off interpolation (w/ interpolation=none), the original image will be embedded. Of course dpi has no meaning in this case. However, I agree with you that dpi should be a property of the backend only, not the figure. But I am not sure if this can be fixed soon. It will be difficult and will take lots of effort I think. Yeah, that's what I feared. But in the mean time, are there any best practices to minimize undesired effects like the one above? For example, are there any other functions that need special parameters to not raster their output when writing to a vector format? And is there a way to get a figure on the screen with the right size when I don't know what dpi the monitor is running with? Best, -Nikolaus -- »Time flies like an arrow, fruit flies like a Banana.« PGP fingerprint: 5B93 61F8 4EA2 E279 ABF6 02CF A9AD B7F8 AE4E 425C -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] xlabels on top, ylabels on right
Hi, me again :) I'm looking for a way to have the xlabels on the top (instead of bottom), and the ylabels on the right (instead of left). I guess I could do something with twinx / twiny and just not use the left/bottom axis, but I'm sure there is some more elegant way ... I need to correct myself: I want the xticklabels / yticklabels to be on top/right. I believe you are looking for tick_params(): http://matplotlib.org/api/axes_api.html?highlight=tick_param#matplotlib.axes.Axes.tick_params ax.tick_params(axis='x', labelbottom=False, labeltop=True) ax.tick_params(axis='y', labelleft=False, labelright=True) Yes, that's it, Ben. Thanks! -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Format date tick labels
On Oct 11, 2012, at 2:58 PM, Benjamin Root wrote: On Thu, Oct 11, 2012 at 4:53 PM, Mark Lawrence breamore...@yahoo.co.uk wrote: On 11/10/2012 10:55, Damon McDougall wrote: Am I missing something here? Are seconds just floats internally? A delta of 1e-6 is nothing (pardon the pun). A delta of 1e-9 is the *least* I'd expect. Maybe even 1e-12. Perhaps the python interpreter doesn't do any denormalisinghttp://stackoverflow.com/questions/9314534/why-does-changing-0-1f-to-0-slow-down-performance-by-10x when encountered with deltas very close to zero... What percentage of computer users wants a delta of 1e-12? I suspect that the vast majority of users couldn't care two hoots about miniscule Preach on, my brother! Preach on! [psst -- you are facing the choir...] I'm a little confused by this attitude. I recognize that there are issues around dates, I've written a few date libraries myself to get around insane excel date issues (pop quiz for anyone at MS, was 1900 a leap year?) or just to simplify APIs for my own use. But do neither of you think that nanoseconds are important to scientists? I know of enough projects that work with pico (and a few with femto) seconds. Even though I often work with climate data covering ~100s of years and used to work with geologic data covering ~billions of years, I may start working with raw laser data for distance measurements where nanoseconds can be a pretty big deal. These data would be collected over a few years time, so a date utility that can handle that scale range would be useful. I guess I'll be writing my own date/time library again and hacking together some way of plotting data in a meaningful way in matplotlib. Don't get me wrong, matplotlib shouldn't have to reinvent the wheel here, but claiming that nobody could possibly care about 1e-12 seconds seems a little provincial. My apologies if that is not how the above statements were intended. regards, Ethan-- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Format date tick labels
On Friday, October 12, 2012, Ethan Gutmann wrote:
On Oct 11, 2012, at 2:58 PM, Benjamin Root wrote:
On Thu, Oct 11, 2012 at 4:53 PM, Mark Lawrence
breamore...@yahoo.co.ukjavascript:_e({}, 'cvml',
'breamore...@yahoo.co.uk');
wrote:
On 11/10/2012 10:55, Damon McDougall wrote:
Am I missing something here? Are seconds just floats internally? A
delta of 1e-6 is nothing (pardon the pun). A delta of 1e-9 is the
*least* I'd expect. Maybe even 1e-12. Perhaps the python interpreter
doesn't do any denormalising
http://stackoverflow.com/questions/9314534/why-does-changing-0-1f-to-0-slow-down-performance-by-10x
when encountered with deltas very close to zero...
What percentage of computer users wants a delta of 1e-12? I suspect
that the vast majority of users couldn't care two hoots about miniscule
Preach on, my brother! Preach on!
[psst -- you are facing the choir...]
I'm a little confused by this attitude. I recognize that there are issues
around dates, I've written a few date libraries myself to get around insane
excel date issues (pop quiz for anyone at MS, was 1900 a leap year?) or
just to simplify APIs for my own use. But do neither of you think that
nanoseconds are important to scientists? I know of enough projects that
work with pico (and a few with femto) seconds. Even though I often work
with climate data covering ~100s of years and used to work with geologic
data covering ~billions of years, I may start working with raw laser data
for distance measurements where nanoseconds can be a pretty big deal.
These data would be collected over a few years time, so a date utility
that can handle that scale range would be useful. I guess I'll be writing
my own date/time library again and hacking together some way of plotting
data in a meaningful way in matplotlib.
Don't get me wrong, matplotlib shouldn't have to reinvent the wheel here,
but claiming that nobody could possibly care about 1e-12 seconds seems a
little provincial. My apologies if that is not how the above statements
were intended.
regards,
Ethan
Oh, don't get me wrong, those time scales are important. I was merely
expressing my dismay over the amount of problems that exists in the set of
tools for everyday use. It is 2012, and Perl still has probably the best
datetime library out there...
Python can do much better.
Ben Root
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Re: [Matplotlib-users] Format date tick labels
On 12/10/2012 20:38, Ethan Gutmann wrote: I'm a little confused by this attitude. I recognize that there are issues around dates, I've written a few date libraries myself to get around insane excel date issues (pop quiz for anyone at MS, was 1900 a leap year?) or just to simplify APIs for my own use. But do neither of you think that nanoseconds are important to scientists? I know of enough projects that work with pico (and a few with femto) seconds. Even though I often work with climate data covering ~100s of years and used to work with geologic data covering ~billions of years, I may start working with raw laser data for distance measurements where nanoseconds can be a pretty big deal. These data would be collected over a few years time, so a date utility that can handle that scale range would be useful. I guess I'll be writing my own date/time library again and hacking together some way of plotting data in a meaningful way in matplotlib. Don't get me wrong, matplotlib shouldn't have to reinvent the wheel here, but claiming that nobody could possibly care about 1e-12 seconds seems a little provincial. My apologies if that is not how the above statements were intended. regards, Ethan I actually said What percentage of computer users wants a delta of 1e-12? I suspect that the vast majority of users couldn't care two hoots about miniscule time deltas in a world where changing time zones can cause chaos How does this translate into claiming that nobody could possibly care about 1e-12 seconds seems a little provincial? -- Cheers. Mark Lawrence. -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Format date tick labels
On Oct 12, 2012, at 4:15 PM, Mark Lawrence wrote: On 12/10/2012 20:38, Ethan Gutmann wrote: I'm a little confused by this attitude. I recognize that there are issues around dates, I've written a few date libraries myself to get around insane excel date issues (pop quiz for anyone at MS, was 1900 a leap year?) or just to simplify APIs for my own use. But do neither of you think that nanoseconds are important to scientists? I know of enough projects that work with pico (and a few with femto) seconds. Even though I often work with climate data covering ~100s of years and used to work with geologic data covering ~billions of years, I may start working with raw laser data for distance measurements where nanoseconds can be a pretty big deal. These data would be collected over a few years time, so a date utility that can handle that scale range would be useful. I guess I'll be writing my own date/time library again and hacking together some way of plotting data in a meaningful way in matplotlib. Don't get me wrong, matplotlib shouldn't have to reinvent the wheel here, but claiming that nobody could possibly care about 1e-12 seconds seems a little provincial. My apologies if that is not how the above statements were intended. regards, Ethan I actually said What percentage of computer users wants a delta of 1e-12? I suspect that the vast majority of users couldn't care two hoots about miniscule time deltas in a world where changing time zones can cause chaos How does this translate into claiming that nobody could possibly care about 1e-12 seconds seems a little provincial? -- Cheers. Mark Lawrence. Like I said, my apologies if I mis-interpreted. To me the statement the vast majority of users couldn't care two hoots... *implies* since almost nobody needs this we won't worry about it, especially when it is in response to someone who felt this was an important feature: A delta of 1e-9 is the *least* I'd expect. Maybe even 1e-12. . My response was as much an issue with how I perceived the tone as anything else (obviously, tone doesn't cary well over email ;) ) Don't get me wrong, I realize there are bigger fish to fry. I just want add a vote that 1E-12 seconds (and less) can indeed be important to a significant number of people. I suspect that many experimental physicists would be unable to use a time utility that can't handle those timescales. Many of them will simply write there own utility, but then if they start running into any of the longer time scale issues e.g. leap years/seconds etc. they end up having to reinvent the wheel. Others have also pointed out that databases[1], network packets and stock trading transactions[2] may care about nanoseconds. [1]http://code.activestate.com/lists/python-dev/117090/ [2]http://code.activestate.com/lists/python-dev/117091/ I'm glad to see that others are thinking about this and that future python versions may get down to nanosecond (or better?) resolution, though I haven't found the PEP for it yet. Guido seems to have given his approval for more work on the matter at least : http://code.activestate.com/lists/python-dev/117147/ PEP 418 mentioned before doesn't mention the date time class as far as I can tell. http://www.python.org/dev/peps/pep-0418/ regards, Ethan -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] color pallette suggestions wanted
Andreas,
Perhaps you would be better off making your own colormap considering that
your data is not symmetric around zero. You could do something like the
following:
--
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.colors as plc
data = np.random.randn(12,72)
data = data*5. - 5.
zero = -1*data.min()/(data.max() - data.min())
cdict = {'red': [(0.0, 1.0, 1.0),
(zero, 1.0, 1.0),
(1.0, 0.0, 0.0)],
'green': [(0.0, 0.0, 0.0),
(zero, 1.0, 1.0),
(1.0, 0.0, 0.0)],
'blue': [(0.0, 0.0, 0.0),
(zero, 1.0, 1.0),
(1.0, 1.0, 0.0)],
}
cmap = plc.LinearSegmentedColormap('cmap', cdict, N=1000)
mappable = plt.cm.ScalarMappable(cmap=cmap)
mappable.set_array(data)
fig = plt.figure()
plt.pcolormesh(data, cmap=cmap)
fig.colorbar(mappable)
plt.show()
--
Of course, the zero calculation assumes that zero actually exists in your
data set. That can be fixed with a simple if...else statement if you want
this to be more robust.
You can get rid of a few lines from this code if you don't want to set a
ScalarMappable object. However, I was doing some stuff with line
collections where I wanted some colors to have an alpha associated with
them, and I found that I was losing that info with the simpler pyplot
interface for colorbar generation. So I left in the slightly more complex
code for reference. (This might be changed in newer versions of mpl, I just
haven't needed to rework my code to check.)
Ryan
On Fri, Oct 12, 2012 at 4:17 AM, Andreas Hilboll li...@hilboll.de wrote:
Hi,
I have some data I want to plot using pcolormesh. It's 2d climatological
data, see the attached plot. My data is in a range from -7 to +0.6. I want
to be 0.0 to be clearly visible, while at the same time, the color range
should show the full dynamic of the values. I played with the bwr and
seismic color maps, centering on zero, so that white is 0.0. However, I'm
not too happy with the dynamic range I get in the negative.
Any suggestions are very welcome ...
Cheers, Andreas.
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[Matplotlib-users] Fwd: color pallette suggestions wanted
Forgot to reply all. -- Forwarded message -- From: *Damon McDougall* Date: Friday, October 12, 2012 Subject: [Matplotlib-users] color pallette suggestions wanted To: Andreas Hilboll li...@hilboll.de On Fri, Oct 12, 2012 at 10:17 AM, Andreas Hilboll li...@hilboll.dejavascript:; wrote: Hi, I have some data I want to plot using pcolormesh. It's 2d climatological data, see the attached plot. My data is in a range from -7 to +0.6. I want to be 0.0 to be clearly visible, while at the same time, the color range should show the full dynamic of the values. I played with the bwr and seismic color maps, centering on zero, so that white is 0.0. However, I'm not too happy with the dynamic range I get in the negative. Your data is not symmetric about zero, so you will always get a result the looks 'too dynamic' in the negative values (that is, if you want to use the whole colour map range). You need to make a sacrifice somewhere to get the effect you want. 1) Move your data so it's symmetric around zero, that way you'll get a nice dynamic change, but the position of 'zero' will be less clear. 2) Don't move your data and use a truncated colour map. That way the position of 'zero' will be clear but you'll get less dynamic change in the negative values. Hope this helps. Best, Damon -- Damon McDougall http://www.damon-is-a-geek.com B2.39 Mathematics Institute University of Warwick Coventry West Midlands CV4 7AL United Kingdom -- Damon McDougall http://www.damon-is-a-geek.com B2.39 Mathematics Institute University of Warwick Coventry West Midlands CV4 7AL United Kingdom -- Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
