Monthly log files: Difference between revisions

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=== Cumulus Wind Speed Terminology ===
=== Cumulus Wind Speed Terminology ===
How wind speeds relate to various weather stations is explained in FAQ. Basically there are 3 values stored:
How wind speeds relate to various weather stations is explained in FAQ. Basically there are 3 values stored:
#Gust - the highest wind speed over a particular period (can be selected, but defaults to 10 minutes),
#Gust - the highest wind speed over a particular period (this period defaults to 10 minutes),
#Average - the moving average of wind speed measurements over a particular period (can be selected, but defaults to 10 minutes),
#Average - the moving average of wind speed measurements over a particular period (this period can be set to what suits you, but defaults to 10 minutes),
#Latest - the most recent (wind speed or gust speed) measurement.
#Latest - the most recent (wind speed or gust speed) measurement.
[[FAQ#What_do_the_various_wind_speeds_in_Cumulus_correspond_to.2C_with_Davis_stations.3F|FAQ: Wind speeds in Cumulus with Davis stations]], the ''EasyWeather'' differences in [[FAQ#What_do_the_various_wind_speeds_in_Cumulus_correspond_to.2C_with_Fine_Offset_stations.3F|FAQ: Wind speeds in Cumulus with Fine Offset stations]] and [[FAQ#How_do_I_set_up_recording_wind_speeds_in_Cumulus.2C_with_Oregon_Scientific_and_La_Crosse_stations| FAQ: Wind speeds with Oregon Scientific and La Crosse stations]]
[[FAQ#What_do_the_various_wind_speeds_in_Cumulus_correspond_to.2C_with_Davis_stations.3F|FAQ: Wind speeds in Cumulus with Davis stations]], the ''EasyWeather'' differences in [[FAQ#What_do_the_various_wind_speeds_in_Cumulus_correspond_to.2C_with_Fine_Offset_stations.3F|FAQ: Wind speeds in Cumulus with Fine Offset stations]] and [[FAQ#How_do_I_set_up_recording_wind_speeds_in_Cumulus.2C_with_Oregon_Scientific_and_La_Crosse_stations| FAQ: Wind speeds with Oregon Scientific and La Crosse stations]]


[[Windrun]] is calculated from average wind speed measurements, every minute if Cumulus is running, or from the values that are logged as average wind speed when Cumulus is restarted and catches up from the station logger.
Cumulus calculates the monthly/annual/period ''average wind speed'' (as used for 'This ...' screens in '''View''' menu and the NOAA report) by trawling through the monthly logs, summing the values for the individually logged average wind speed (the fifth item ''after'' the date in each entry, column F in a spreadsheet), and dividing by the number of entries for the required calendar days. It therefore assumes that each entry has equal 'weight', i.e. each one covers the same period.  If your monthly log(s) is/are a mixture of values stored while Cumulus is running and values copied from the station logger during periods when Cumulus was not running, then it is possible the two logging intervals have not been set to the same time, so the output value could be skewed for that month/year/period.
 
[[Windrun]] is also calculated from average wind speed measurements, in this case every minute if Cumulus is running, or from the values that are logged (at station logging interval) as average wind speed when Cumulus is restarted and catches up from the station logger.


===Using Monthly logs to deal with shorter (or incomplete) dayfile.txt records for particular dates===
===Using Monthly logs to deal with shorter (or incomplete) dayfile.txt records for particular dates===
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