Trouble with For-Loop

Hi there,

I wrote a little procedure that is supposed to subtract a wave from another for a set of data.

My dataset kinda looks like this:
a_wave0,a_wave1,a_wave2, etc
b_wave0,b_wave1,b_wave2,etc

What I want to accomplish is subtract b_wave0 from a_wave0, b_wave1 from a_wave1, etc. However, the final results don't seem to make sense. When I look at the debugger, it appears that that the loop is doing something like this:
b_wave0 from a_wave0, b_wave0 from a_wave1, b_wave0 from a_wave2, etc.

I was thinking that including an "if" statement within the loop might help, but I'm not quite sure how to do it.

Here is the procedure I wrote:
#pragma rtGlobals=3     // Use modern global access method and strict wave access.

Function AmorphousSpectra(w1,w2)        //Determines amorphous spectra by subtracting Spano fit from total spectra

    WAVE w1,w2                      //w1=TotalSpectra and w2=Spano Fit
    String outputName= NameOfWave(w1)+"_A"
   
    Duplicate/O w1 $(outputName)
    Wave output = $(outputName)

    output = w1 - w2   
End

Function AmorphousAll(w1,w2,fnum)       //To use it do not include any numbers or _bl_smth in the name

    STRING w1,w2
    Variable fnum
    Variable i                          //The initial values of i and j should be adjusted based on the numbers present in the original names of the wave
    Variable j
    String neww1,neww2
   
    for(i=16; i<=fnum;i=i+1)
        neww1= w1 +num2str(i)+"_bl_smth"   
   
    for(j=16; j<=fnum;j=j+1)
        neww2= w2 +num2str(j) +"_bl_smth"  
            AmorphousSpectra($(neww1),$(neww2))
    endfor
    endfor
End


Thanks for any suggestions/help!
Nevermind. Got it...

#pragma rtGlobals=3     // Use modern global access method and strict wave access.

Function AmorphousSpectra(w1,w2)        //Determines amorphous spectra by subtracting Spano fit from total spectra

    WAVE w1,w2                      //w1=TotalSpectra and w2=Spano Fit
    String outputName= NameOfWave(w1)+"_A+test"
   
    Duplicate/O w1 $(outputName)
    Wave output = $(outputName)

    output = w1 - w2   
End

Function AmorphousAll(w1,w2,fnum)       //To use it do not include any numbers or _baselined_smth in the name

    STRING w1,w2
    Variable fnum
    Variable i                          //The initial values of i and j should be adjusted based on the numbers present in the original names of the wave
    Variable j
    String neww1,neww2
       
        for(i=16; i<=fnum;i=i+1)
            neww1= w1 +num2str(i)+"_bl_smth"   
        for(j=16; j<=fnum;j=j+1)
            neww2= w2 +num2str(j) +"_bl_smth"  
            if(i==j)   
                AmorphousSpectra($(neww1),$(neww2))
            else
                return 0
            endif
        endfor
        endfor 
End