count rows in matrix ?

Asked by Rakesh Praveen

Rakesh Praveen (view profile)

on 7 Nov 2011
Latest activity Answered by Thulitha Theekshana

Thulitha Theekshana (view profile)

on 17 Jul 2019
Accepted Answer by Oleg Komarov

Oleg Komarov (view profile)

hey, i want to know is there a way to get how many rows are there in a given matrix. like for example when we say 'length(A)' it can give number of columns in a matrix(A), likewise can we know about number of rows ?
thank you.

Anand Gehlot

Anand Gehlot (view profile)

on 16 Oct 2016
Use height(T)
https://www.mathworks.com/help/matlab/ref/height.html
Image Analyst

Image Analyst (view profile)

on 16 Oct 2016
height() doesn't work on matrices -- it only works on tables.
morteza HEIDARI

morteza HEIDARI (view profile)

on 15 Aug 2017
If for example your matrix is A, you can use : size(A,1) for number of rows. size(A,2) for number of columns. Also there are some other ways like : length ( A(:,1) ) for number of rows.

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Answer by Oleg Komarov

on 7 Nov 2011

size(A,1)

Rakesh Praveen

Rakesh Praveen (view profile)

on 7 Nov 2011
thank u very much oleg komarov
Hoang-Linh To

Hoang-Linh To (view profile)

on 19 May 2014
Thank you so much, that's also what I want :)
Pooja

Pooja (view profile)

on 22 Sep 2014
It workd for me also. Thankyou Oleg Komarov

Answer by Image Analyst

Image Analyst (view profile)

on 7 Nov 2011

For a 2D matrix:
[rows columns] = size(array2D);
or, in general,
sizeOfMatrix = size(yourMatrix);

Rakesh Praveen

Rakesh Praveen (view profile)

on 7 Nov 2011
thank u very much image analyst

Answer by Ashutosh Kumar

Ashutosh Kumar (view profile)

on 22 Jul 2016

length(A) gives you maximum out of the matrix made by calling the size,so it doesn't give you column(A) and for calling column(A) you need size(A,2) and for row you need size(A,1)...like suppose you have a 5*4 matrix then length(A) will give you 5 number of rows not 4...Hope that will help others I myself used length(A) and ended up making a wrong code and took me 2 hours to do it right

Answer by Thulitha Theekshana

Thulitha Theekshana (view profile)

on 17 Jul 2019

I think the best way is to use size(x,y) function.
ex: if you want to get the height, size(matrix_name, 1). Here the second variable denotes the dimensioin you need to measure. From one it means the number of rows or the first dimension. From 2 it means the number of columns or the length. So I think you get the idea,