Question

I am trying to make a histogram in matlab. My data size is huge (3.5 million), x and y data are the same size (both are 3.5 million)

My original data has 200,200,88 3D matrix, I reshaped it to 1 column
the code for this:

[dose , size] = Dose('C:\R1')
s = size(1)*size(2).size(3)
t = reshape(dose, s, [])

When I try the command hist(t), I got a 1 bar only.

My workspace is as the following:

dose   <200x200x88 double>
s      3520000
size   [200,200,88]
t      <3520000x1 double>

Could you tell me how to make a histogram with this data?

Answer 1

In order to get a single long vector from your 3D array you can use just the (:) operator. Try the following code:

num_of_bins = 100 ; %change to whatever # you want
hist(dose(:),linspace(min(dose(:)),max(dose(:)),num_of_bins));

The hist will take only the relevant limits of dose (min to max) and you can control the # of bins at will. I’ve used linspace to create a linearly spaced bin vector, but this can be modified also to a different set of bins by assigning a different range vector.