Generating a common x axis from interpolation2 command

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Hello, I am fairly new for Igor and I need help with interpolation2 command. I am plotting Cyclic voltammetry data in Igor. These curves have different x axises after iR corrections. Therefore I want to generate a common x axis. I want to know how to exactly use the interpolation2 command for this.

Thank you in advance

Use /I=3 (X values taken from destination wave) and /X=<wave> where <wave> is some wave that you create that has the desired X values.

May 4, 2023 at 09:38 am - Permalink

If you want the output to be waveforms as opposed to XY pairs, you can use /Y=yDest, omit /X=xDest, and specify /I=3 (X from Dest). This creates a waveform output where the X values are determined by the X scaling that you set before calling Interpolate2.

I am attaching an experiment file that illustrates this. See the Demo function in the procedure window.

If you are not familiar with the distinction between XY pairs and waveforms, execute this:

DisplayHelpTopic "The Waveform Model of Data"

and continue to read the following section, "The XY Model of Data".

Here is a copy of the Demo function in the attached experiment file:

Function Demo()
    // Create input XY data
    Make/O/N=10 xData0 = p + gnoise(.1), yData0 = sin(x)
    Make/O/N=10 xData1 = p + gnoise(.1), yData1 = sin(x) + .25
 
    // Display input XY data in table
    if (WinType("DemoTable") == 0)
        Edit/N=DemoTable xData0, yData0 
        AppendToTable/W=DemoTable xData1, yData1
    endif
    
    // Display input data in graph
    if (WinType("DemoGraph") == 0)
        Display/N=DemoGraph/W=(19,45,917,624) yData0 vs xData0
        AppendToGraph/W=DemoGraph yData1 vs xData1
        ModifyGraph mode(yData0)=3,marker(yData0)=19
        ModifyGraph mode(yData1)=3,marker(yData1)=19
        ModifyGraph rgb(yData1)=(1,16019,65535)
    endif
    
    // Make destination waves and set their X scaling
    Make/O/N=50 dest0, dest1
    SetScale x, 0, 9, "", dest0, dest1
    AppendToTable/W=DemoTable dest0.id, dest1.id
    
    // Do interpolation using waveform output with X From Dest
    Interpolate2/T=1/Y=dest0/I=3 xData0,yData0
    Interpolate2/T=1/Y=dest1/I=3 xData1,yData1
    
    // Append output to graph
    CheckDisplayed/W=DemoGraph dest0
    if (V_Flag == 0)
        AppendToGraph/W=DemoGraph dest0
        ModifyGraph/W=DemoGraph mode(dest0)=4,marker(dest0)=10
    endif
    CheckDisplayed/W=DemoGraph dest1
    if (V_Flag == 0)
        AppendToGraph/W=DemoGraph dest1
        ModifyGraph/W=DemoGraph rgb(dest1)=(1,16019,65535)
        ModifyGraph/W=DemoGraph mode(dest1)=4,marker(dest1)=10
    endif
End

 
Interpolate Multiple XY Pairs Using Same Dest X Scaling.pxp (8.23 KB)

May 4, 2023 at 04:30 pm - Permalink

Thank you very much for the really helpful comments. I was able to resolve my issue with these. Thank you very much once again.

July 12, 2023 at 01:00 pm - Permalink