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Charts - Wind charts: Difference between revisions
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Every record in the database is taken as a sample and counted for the speed and direction classes and as such presented in the chart. Especially for the high frequency sampling (one or five minutes) this will give an accurate picture of the wind speed and direction figures. For the lower frequency sampling this picture may be less accurate for the month level. | Every record in the database is taken as a sample and counted for the speed and direction classes and as such presented in the chart. Especially for the high frequency sampling (one or five minutes) this will give an accurate picture of the wind speed and direction figures. For the lower frequency sampling this picture may be less accurate for the month level. | ||
NOTE: because of this calculation this graph takes a high toll on the performance of CumulusUtils: first because reading the monthly logs is expensive - especially when sampling on minute or five minute frequency - and secondly because the list is long (millions of records when using minute sampling) and making the sub selections per month again takes its toll. Optimisation of this chart is continuous work in progress. | NOTE: because of this calculation this graph takes a high toll on the performance of CumulusUtils: first because reading the monthly logs is expensive - especially when sampling on minute or five minute frequency - and secondly because the list is long (millions of records when using minute sampling) and making the sub selections per month again takes its toll. Optimisation of this chart is continuous work in progress. Performance of CumulusUtils is highly dependent on the hardware it is running on. | ||
== Wind Run == | == Wind Run == | ||