555
edits
FAQ: Difference between revisions
→The peak values on my graphs are not the same as my extreme values
No edit summary |
|||
| Line 434: | Line 434: | ||
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. | 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. | 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. The exception to this is with Davis stations, in the situation where the 'high gust' figure has been read directly (as a way of ensuring that the high gust isn't missed) rather than by the usual reading of the current data. In this case, the gust is recorded as the high, but is not written to the current value, and hence does not appear on the graph, as it may be out of sequence with the current data. | ||
== My extreme values do not appear in the 'monthly' data logs == | == My extreme values do not appear in the 'monthly' data logs == | ||