How to get the mean and std. of bits (fragments) of data?

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Hi, I have long waves with uneven bits of data. I would like to get the mean and std. of each bit, how could I do this? I guess it should be a loop that goes from one bit to the next, but I don’t know how to do this.

 bits of data

I'm not super certain of what you're asking for... below is a snippet that will return a 2D free wave with the average and standard deviation of each contiguous chunk of data only; so, e.g.if there are two contiguous chunks like shown in your image, then the result will be a 2x2 matrix. There may be more efficient ways to do this, and you may not want just the values if you have timeseries data for example.

//___________________________________________________________________________________________________
// Get average and standard deviation of each chunk of data.
Function/WAVE StatsNonNaNs(Wave inWv)   
 
    int i,k,q,n=numpnts(inWv)
    Make /FREE /N=(0,2) outWv = NaN
        
    do
        if (numtype(inWv[i]) == 0)
            k=i                     
            do                          
                k++
            while ( (k < i) && (k < n) )
            q=k-1
            if (numtype(inWv[k]) == 0)      
                do                          
                    k++
                    if (k == n)
                        break   
                    endif
                while ((numtype(inWv[k]) == 0) && (k < n)) 
                k--                     
                if ((k-q)  >= 1)        
                    InsertPoints /M=0 Inf, 1, outWv
                    WaveStats/Q/R=[q, k]/M=2 inWv
                    outWv[Inf][0] = V_avg
                    outWv[Inf][1] = V_sdev
                endif
                i=k
            else        
                i=k
            endif   
        else
            i++
        endif
    while (i < n-1) 
    
    return outWv
end
//___________________________________________________________________________________________________

 

December 6, 2021 at 01:33 am - Permalink