Many Thanks. I had an interval field in my history, so I used that, which
seemed to work OK.  I have successfully loaded the 2018 history; now the
rest.

David.

On Sat, 14 Apr 2018 at 00:46, gjr80 <gjroder...@gmail.com> wrote:

> David,
>
> Perhaps a bit late but the answer is it depends. 'derive' will attempt to
> derive the interval from the incoming data, it's not a very sophisticated
> algorithm, it is simply the difference in timestamps of successive records.
> So derive can suffer if you have big gaps. 'conf' will use the archive
> interval in your weewx.conf (or whatever weeWX config file wee_import is
> told to use). This will be fine if all of your source data say came from
> weeWX and uses the same interval as the archive interval specified in
> weewx.conf. The advantage here is that large data gaps don't have the
> disruptive impact they did with 'derive'. Of course the downside is that
> your source data and weewx.conf may have different intervals. 'x' (where x
> is the number of minutes) allows you to force all imported records to use x
> as the interval. Again this can be handy if your source data has a fixed
> interval but there are large data gaps. Also useful for importing tranches
> of source data that may have different intervals.
>
> In summary - beware of 'derive', you really need a good solid (regular)
> data source for it to be effective.
>
> You will find the interval config option
> <http://weewx.com/docs/utilities.htm#[CSV]> described in the wee_import
> section of the Utilities Guide <http://weewx.com/docs/utilities.htm>.
>
> Gary
>
>
> On Friday, 13 April 2018 18:22:49 UTC+10, dhin...@djhindley.com wrote:
>>
>> Gary
>>
>> Many Thanks for your very helpful reply.  So which setting do I use for
>> the archive interval in the config file? "derive" seems the most logical,
>> but the instructions say that "derive" is suitable when the data was
>> recorded at fixed intervals.
>>
>> I do have some gaps in my data - up to two weeks in some cases.  I plan
>> to try to fill as many of these gaps as possible using a combination of
>> downloaded data from weathercloud (for my weather station) and also using
>> the Met office's 5km grid data as a suitable proxy (for the grid containing
>> my PWS).  I will attempt to process this all into a single archive database
>> using R software and then use weewx import. If I need to take up your kind
>> offer of a Weatherlink import module, I will let you know.
>>
>> David.
>>
>> On Friday, 13 April 2018 02:37:20 UTC+1, gjr80 wrote:
>>>
>>> David,
>>>
>>> Variable archive intervals have been supported since weeWX v3.0.0,
>>> though I believe there was a display/report calculation bug that was
>>> addressed in 3.7.0 (of course we are all running 3.8.0 so neither of these
>>> should be an issue :))
>>>
>>> One thing to be mindful of when using wee_import to import data is that
>>> when you are deriving the archive interval from the source data (ie finding
>>> the difference between successive timestamps) missing records can skew this
>>> significantly. A single missing record in a data set with an interval of 5
>>> minutes will likely have negligible effect but if you have several hours or
>>> days missing it may be a different matter. For this reason when importing
>>> from WeatherUnderground if your WeatherUndergroud data was posted every 10
>>> minutes it is quite often handy to force wee_import to use a 10 minute
>>> archive interval as WeatherUnderground often does not return all available
>>> data, plus it is not unusual for users to have large gaps in their
>>> WeatherUnderground data.
>>>
>>> If you have a changing archive interval in your data and are concerned
>>> about data gaps, it might be useful to break the import down into smaller
>>> chunks that use a single archive interval and import that data with a set
>>> rather derived interval.
>>>
>>> Gary
>>>
>>> PS. If there is significant reformatting required to import the
>>> ex-WeatherLink data I am happy to put together a WeatherLink module for
>>> wee_import, I will just need to know the data format. Only thing is it will
>>> take time for me to put the module together, though I guess your old data
>>> is not going anywhere :)
>>>
>>> On Friday, 13 April 2018 01:16:54 UTC+10, Andrew Milner wrote:
>>>>
>>>> As far as I know the latest version of weewx casn handle variable
>>>> intervals- so just let wee_import derive the interval from the time stamps*
>>>> should* work (I think!!)
>>>>
>>>> someone more knowledgeable maywish to comment ....
>>>>
>>>>
>>>>
>>>> On Thursday, 12 April 2018 17:59:03 UTC+3, dhin...@djhindley.com wrote:
>>>>
>>>>> The import facility looks like the right way to go - but unfortunately
>>>>> my source data has variable archive intervals. Is there any way of dealing
>>>>> with this in the weewx import utlility, or is it best to convert all the
>>>>> source data to have the same archive interval (painful!)?
>>>>>
>>>>> Thanks.
>>>>>
>>>>> On Wednesday, 11 April 2018 17:45:19 UTC+1, dhin...@djhindley.com
>>>>> wrote:
>>>>>>
>>>>>> Hi
>>>>>>
>>>>>> I have just started using weewx on a Raspberry Pi with a Davis
>>>>>> Vantage using Weatherlink IP. The weather station has been running for 2
>>>>>> years, but I only got weewx working from today. All is working fine, 
>>>>>> except
>>>>>> that since I updated my archive record to 5mins immediately prior to the
>>>>>> installation, weewx only shows the recent records. Does anyone know if
>>>>>> there is a way I can manually add the historical data to the weewx
>>>>>> database, so that the full history is shown on my weewx webpage?
>>>>>>
>>>>>> Thanks
>>>>>>
>>>>> --
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