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Scaling data in svg plot. ( unit conversion )

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Wallyllama:
I have a bme280 tenp/pressure/humidity sensor reporting via MQTT. I graph them with gplot. Sofar, so good. The problem is pressure is reported in Pascals. I could modify the code that reads the me, but I'm hoping there is a way to app,y a scale to each reading as the gis made. made. For example multiplying Pascals by 0.00296 gives in hes of mercury, or dividingb by100 gives hPa,

xenos1984:
You can use the fourth parameter in a plot data entry to specify a function, which is applied to each data point. For example, if your plot line reads


--- Code: ---#FileLog 4:pressure:0:

--- Ende Code ---

you can divide each pressure value by 100 like this:


--- Code: ---#FileLog 4:pressure:0:($fld[3]*0.01)

--- Ende Code ---

rudolfkoenig:
The function field is also present in the SVG-Editor, it is the last text-input field in the row.
Note: $fld[ x ] is a perl array, the index starts with 0.

Wallyllama:
perfect! thank you, I knew it would be somewhat obvious once i knew the answer.  :)    oh and sorry about duplicating this. I don't see that I can delete the other one.   :(

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