Histogram with variable bin width

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Thu, 06/15/2017 - 10:54 pm

I know Igor has the function for making a histogram with an evenly spaced bin width. Is there any function for making a histogram with variable bin width?
For example, I have a data set (1000 points) that range over 1 to 20. I want to make a histogram of these data set using user-defined variable bin width. For example,
bin1 x<5, bin2 515 (something like that).

Thanks
PS
I think the is no built-in function (since the result is a single wave). However, use the histogram function with a small (commensurate) bin size and collect the bins afterwards to your need. Create an x-wave corresponding to the new bins and you are done...
HJ

June 16, 2017 at 02:08 am - Permalink

If you are using IP7 you may consider a tricky approach by using JointHistogram, an operation that does allow you to provide your own bins wave. With JointHistogram duplicate your data wave (we will consider it to be the X wave) to create a fake Y wave and set it equal to 1 (or some other constant). You would then use the flag /XBWV to specify your bins wave for the X wave (the only one you are interested in). Since your Y wave is a constant, the Y distribution should not matter. Here is an example:
•make /n=100 xxx=enoise(10)
•// create bins wave:
•make /N=5 xBins={1,3,5,7,10}
•duplicate xxx,yyy
•yyy=1
•jointhistogram /xbwv=xbins xxx,yyy
MatrixOP/O hist1DResult=col(M_JointHistogram,0)


A.G.
WaveMetrics, Inc.

June 16, 2017 at 08:19 am - Permalink