Histogram implementation in Matlab vs Perl

Hello,

I have perl code that reads in a file, line by line and creates a histogram by mapping the keys to a hash.

while (get line){
  %hist1=map{$_=>0} @$column
}

How to do this in matlab? I have parsed the input with regexp/regexprep but now how I map this to an array?

Thanks.

Answer 1

[Image Analyst]

In the loop, after you've read the input values on the line into some array (which it sounds like you say you've done already):

counts = hist(yourArray, numberOfBins);

[Image Analyst]

g'a "Answer" moved here:

When I put counts = hist(yourArray, numberOfBins) inside the loop, it only keeps a copy of the last array not a cumulative count.

[Image Analyst]

Well what do you want? I thought you were just going to use it somehow inside the loop. Do you need to keep them all once the loop has ended and use them again? If so, index it:

counts{index} = hist(yourArray, numberOfBins); % Stick into cell array.
index = index + 1;

For more on cell arrays: http://matlab.wikia.com/wiki/FAQ#What_is_a_cell_array.3F

Or you can put into a regular numerical 2D array:

counts2d = ones(1, numberOfBins);  % Put before the loop starts

In the loop:

counts2d(index, :) = hist(yourArray, numberOfBins); % Stick into one row.
index = index + 1;

I can't always read minds - you have to tell me exactly what you want.