how to handle changing wave reference in typical commands

Here is an example that may illustrate what you want. It returns a string list of the waves created.

jjweimer wrote:

Here is an example that may illustrate what you want. It returns a string list of the waves created.

// no error checking on exceeding wave length
Function/S extract_wlist(wave srcwave, variable spoint, variable pwidth, variable nwaves)

    string rootname = NameOfWave(srcwave)
    string rstr = "", tstr
    variable ps, pe
   
    variable ic
   
    for (ic=0;ic<nwaves;ic+=1)
        sprintf tstr, "%s_%02d", rootname, ic
        ps = spoint + ic*(pwidth - 1); pe = ps + pwidth - 1
        duplicate/R=[ps,pe]/O srcwave, $tstr
        rstr += tstr + ";"
    endfor
    return rstr
end

// on command line

> make/N=101/D swave = sin(p)
> print extract_wlist(swave, 0, 5, 6)
-->   swave_00;swave_01;swave_02;swave_03;swave_04swave_05;

 

I always have trouble to perform arithmetic operations with the waves that are created through some kind of automated process (in this case using a loop). 

> ... what kind of command ...?

I would need to see the specifics in your processing to help with anything beyond this.

jjweimer wrote:

> ... what kind of command ...?

variable sumT
sumT = swave_00[5] + swave_01[6] + ...

I would need to see the specifics in your processing to help with anything beyond this.

Updating then on my previous post, you might use this as an example ...

I think your question is how to create an arbitrary number of wave references.

Maybe the function that creates the waves can return a wave of type WAVE that contains wave references. As each wave is created you add a reference to the wave of references.

Thank you so much.. I'll try to work on it and let you know...

I tried to work on it but challenged to find a way to do things. Here is the code that I used to create arbitrary number of waves based on the start and endpoints. 

function ExtractBlocks(batch_time, delta_VOC)

	wave batch_time, delta_VOC

	//make/d/o/n=10 batch_data=0

    Extract/INDX batch_time, startPoints, (p==0 || batch_time[p-1]==0) && batch_time[p]!=0

    Extract/INDX batch_time, endPoints, (p==(numpnts(batch_time)-1) || batch_time[p+1]==0) && batch_time[p]!=0

    variable i,j

    for(i=0;i<numpnts(startPoints);i++)

        Duplicate/O/R=[startPoints[i],endPoints[i]] batch_time $NameOfWave(batch_time)+num2str(i)

        Duplicate/O/R=[startPoints[i],endPoints[i]] delta_VOC $NameOfWave(delta_VOC)+num2str(i)

    endfor
end

By running the code above, I created waves that are named as delta_VOC0, delta_VOC1, delta_VOC2, delta_VOC3..... Now, I would like to check each value in delta_VOC0, delta_VOC1, delta_VOC2, delta_VOC3..... if it is positive or negative. And add positive values and negative values separately for individual wave. I thought to use a for loop to do that, but then depending upon the time range I choose, I might have 100s of delta_VOCs (delta_VOC1, delta_VOC2, delta_VOC3, delta_VOC4, delta_VOC5, delta_VOC6.....), So, I can't do it in a simple way of referencing each delta_VOC wave. I believe I need another for loop where I can change the wave reference (delta_VOC0 then delta_VOC1 then delta_VOC2 then ......) until I cover all delta_VOC waves.

And when I use this automatic referencing method, how to obtain each value or element of the wave, like in normal circumstances, for example, we may use delta_VOC0[7] to read the value of 8th point, but when I have automatic referencing, then what syntax should I use to do that?

vpratap397 wrote:

Now, I would like to check each value in delta_VOC0, delta_VOC1, delta_VOC2, delta_VOC3..... if it is positive or negative. And add positive values and negative values separately for individual wave.

It's not clear to me what you need here. Could you maybe give a more explicit example of how you would process a pair of time and delta_VOC waves? Do these waves all need to be saved, or are they an intermediate step in some calculation?

vpratap397 wrote:

And when I use this automatic referencing method, how to obtain each value or element of the wave, like in normal circumstances, for example, we may use delta_VOC0[7] to read the value of 8th point, but when I have automatic referencing, then what syntax should I use to do that?

Any wave reference that you create is no different to the 'normal' case.

It may be worthwhile reading the help about wave references. Copy these commands, paste them into Igor's command line and press Enter:

DisplayHelpTopic "Wave References"

DisplayHelpTopic "Accessing Waves In Functions"