I could not understand why this part of a code gives error "Undefined function or variable 'normalise'". Can you please figure out for me?

function [normim, mask, maskind] = ridgesegment(im, blksze, thresh)
  im = normalise(im,0,1);  % normalise to have zero mean, unit std dev
  fun = inline('std(x(:))*ones(size(x))');
  stddevim = blkproc(im, [blksze blksze], fun);
  mask = stddevim > thresh;
  maskind = find(mask);

Answer 1

[dpb]

There is no TMW-supplied function normalise nor ridgesegment so if you got the above function from some other place then perhaps you didn't get the entire package. Or, write the function yourself; it's not difficult, it's simply subtracting the mean and dividing by the standard deviation of the sample.

Answer 2

[Adam]

I'm not sure what I can add really to the error message which is succinct and tells you exactly what the problem is.

On the first line of your code you call:

im = normalise(im,0,1);

Matlab can't find that as a function. Either it doesn't exist or you have forgotten to add it to your Matlab path.