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FAQ: Difference between revisions
→The peak values on my graphs are not the same as my extreme values
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== The peak values on my graphs are not the same as my extreme values ==
The graphs are snapshots of the data, taken once a minute while Cumulus is running; it is not feasible to plot every data point. If the extreme value did not coincide exactly with the point at which the data was added to the graph, then it will not appear on the graph
This is most noticeable with wind gusts, the value of which can change rapidly, even over a period of a minute. The 'Plot latest gust' setting causes the 'Latest' figure (as shown on the main screen) to be plotted. What this figure represents exactly depends on your weather station type. This figure may vary rapidly, e.g. on Davis stations, it changes every 3 seconds or so. The graphs are plotted once a minute, and hence, with Davis stations, for example, there is approximately a one in 20 chance of any given 'latest' figure actually being plotted.
Cumulus also stores the peak value of the 'latest' figure from the last 10 minutes. It calls this the 'gust', as this is a reasonable representation of a true 'gust' figure. If you untick 'plot latest gust', it will plot this figure instead. As it contains the peak figure from the last 10 minutes, and the graph is plotted once a minute, plotting this value means that the high gust figure will always appear on the graph.
== My extreme values do not appear in the 'monthly' data logs ==
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