Patrick, On Sunday, 13 January 2019 03:53:38 UTC+10, Patrick Tranchant wrote: > hello Gary or Pat > here are some values found and comparison with my scripts ( excel file > in attach) > I don't have always data with rain and wind !!! >
It is very hard to draw any conclusions from your spreadsheet. I am not sure what data your US and FR rows represent but seeing as you mention dateTime, usUnits and interval I am guessing that these have come from the archive table in your database. If this is the case you need to take some care in comparing them to other data. The data in an archive record (each row in your archive table) is based on the accumulation of all of the loop packets generated by your driver over the archive period (in your case 5 minutes). In most cases the archive record value is an average of all the loop values seen (eg temperature, pressure, wind speed) but some are an accumulation (eg rain). If you wish to compare the results from your python program to weeWX then you need to compare with point-in-time values or the loop data rather than anything in the archive table (this assumes that your python program reads instantaneous values and does not average over time). You would also need to make sure you were obtaining values at the same point in time, I don't know how often your sensors update but if your python program reads the sensors 5 seconds before the weeWX driver does then the sensor may have changed value. Assuming that your python program and weeWX reside on the same machine what you could do is open two terminal windows and arrange them so you can see both on screen at the same time. In one window run weeWX directly so you can observe the values in individual loop packets. In the other window run your python program and have it display its results on screen. Focus on one observation at a time and compare the values in both windows, temperature, humidity and pressure are good starters as they should not change too rapidly; wind speed and rain are poor choices as they change too rapidly and too slowly respectively. If you wanted to record data from comparison later be sure to include some sort of timestamp/system date-time on your python observations. If you capture the weeWX screen output then you should have a timestamp for the loop packets generated by your driver. I hope this helps. > *Oops I just saw that I forgot to put* "record_generation = software"; > > *but it changes nothing, I think* > > *have a good week-end.* > Now that I think of it on your system having record_generation = hardware would not matter as if your driver is not capable of generating a hardware archive record (and your driver is not capable) weeWX automatically falls back to generating one in software. At least having record_generation = software in weewx.conf makes it clear how your system/driver is to function. Gary -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
