How to detect the point with the lowest value in a large number of data?

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Thu, 07/26/2012 - 12:53 am

Hi all,

I have a wave that I want to subtract its minimum from it such the new wave will have the same number of data points but a minimum of 0.

Does anyone know how to do it automatically in Igor instead of going through the whole data set?

Thanks,
The operation WaveStats returns a load of information about the wave such as maximum value (V_max), minimum value (V_min) etc. Something like this should do what you want:

WaveStats inputWave
inputWave -= V_min


where inputWave is the name of the wave you want to operate on. After doing this you can check it worked by performing wavestats on the wave again. This time V_min should be 0. For more information execute DisplayHelpTopic "WaveStats" from the command line.

Tom

July 26, 2012 at 01:20 am - Permalink

WaveMin will be faster than WaveStats.

You need to store the output from WaveMin in a variable, then subtract from the wave:
Variable wMin = WaveMin(w)
w -= wMin

July 26, 2012 at 05:47 am - Permalink