Interpolate between X-values for location of local maximum

[Chris_P_SD]

Hello,

I'm using ChnPeakFind() to return the location of a waveform channel's local maximum.  The result is always a whole number of the X-values channel.  Is there another built-in function in DIAdem that interpolates the X-values to find a more precise location of the peak?

Thanks,

Chris

[Christian-P]

It's called ChnPeakDetect 😉

http://zone.ni.com/reference/en-XX/help/370858M-01/dlgmaths/calc_basis_dlg/dlgchnpeakdetect_dialog/

http://zone.ni.com/reference/en-XX/help/370858M-01/comoff/chnpeakdetect/

Regards

[Brad_Turpin]

Hi Chris,

Most DIAdem users take the array index or indices that are returned by the peak finding function and use them to look up the XY values of each peak from the Xchannel and Ychannel for the curve they are investigating.  If you're investigating a waveform curve with only a Ychannel, then you can use the index and a linear formula based on Xstart and Xdelta to determine the X value at that array index.

Brad Turpin

DIAdem Product Support Engineer

National Instruments

[Brad_Turpin]

Hi Chris,

I'm sorry, I completely read past the "interpolation" content of you question.  This also is something you can apply after receiving the array index of the closest integer match.  I recently answered a question like this with code that does this.  If you prefer the ChnFind() approach to the other command offered above, let me know and I can probably dig out my answer to the other post.

Brad Turpin

DIAdem Product Support Engineer

National Instruments