How to sort a data set for plotting

I have here two data sets, one I want to use as my X and the other the Y axis.

For the X, which is my TNF placeholder values below, I want to simply sort the data array from least to greatest. Which I already know how to do. The Y values, TPF, are also shown below and correlate specifically to the respective index of the TNF array.

TNF = [e, a, d, c, b]
TPF = [e, a, d, c, b]

Sorted, it looks like:

TNF = [a, b, c, d, e]

So how to I get the TPF values to sort with the TNF values and not independently from least to greatest?

Answer 1

[Star Strider]

Ise the second output of the sort function to return the indices, then use those to map ‘TPF’:

TNF = ['e', 'a', 'd', 'c', 'b']
TPF = ['e', 'a', 'd', 'c', 'b']

[TNFsorted, idx] = sort(TNF);
TPFsorted = TPF(idx)

[Jacob Davidson]

Alright, that made sense when I read it. I tried it, however, and I think I'm going about it wrong. Here's what I have:

[TNFSorted, idx] = sort(TNF);

for i = 1:numel(TPF)
    
    TPFSorted(i) = TPF(idx);
    
end

I'm also receiving the following error:

Unable to perform assignment because the indices on the left side are not compatible with the

size of the right side.

Error in BMITestScript (line 5)

TPFSorted(i) = TPF(idx)

I'm not super experienced with MATLAB and mainly use the documentation here on Mathworks as a guide, so I don't know how to interpret this error very well.

EDIT:

Actually, I did the following without the loop, I was unaware I didn't need to iterate through the entier array to accomplish this. I put in exactly what your code had in the response and it worked perfectly. Thank you so much!

I appreciate your help!

[Star Strider]

As always, my pleasure!

[Dav]

Thanks Star.

[Star Strider]

@Dav — My pleasure!