MATLAB Answers

count rows in matrix ?

3,103 views (last 30 days)
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.

  3 Comments

Anand Gehlot
Anand Gehlot on 16 Oct 2016
Use height(T)
https://www.mathworks.com/help/matlab/ref/height.html
Image Analyst
Image Analyst on 16 Oct 2016
height() doesn't work on matrices -- it only works on tables.
morteza HEIDARI
morteza HEIDARI 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.

Sign in to comment.

Accepted Answer

Oleg Komarov
Oleg Komarov on 7 Nov 2011
size(A,1)

  3 Comments

Rakesh Praveen
Rakesh Praveen on 7 Nov 2011
thank u very much oleg komarov
Hoang-Linh To
Hoang-Linh To on 19 May 2014
Thank you so much, that's also what I want :)
Pooja
Pooja on 22 Sep 2014
It workd for me also. Thankyou Oleg Komarov

Sign in to comment.

More Answers (5)

Image Analyst
Image Analyst on 7 Nov 2011
For a 2D matrix:
[rows columns] = size(array2D);
or, in general,
sizeOfMatrix = size(yourMatrix);

  1 Comment

Rakesh Praveen
Rakesh Praveen on 7 Nov 2011
thank u very much image analyst

Sign in to comment.


Ashutosh Kumar
Ashutosh Kumar 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

  0 Comments

Sign in to comment.


Thulitha Theekshana
Thulitha Theekshana 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,

  0 Comments

Sign in to comment.


Gaganjyoti Baishya
Gaganjyoti Baishya on 20 Jun 2020
It's simple. You can see the size of the first column, that will be the rows in matrix.
rows = size(myMatrix, 1); % first row length

  0 Comments

Sign in to comment.


Anurag Pratap Singh
Anurag Pratap Singh on 25 Jun 2020
Hi Rakesh
For counting the number of rows in a matrix you can use the size funtction and pass your matrix in it
[NumRows NumCols]=size(your_matrix);
The first output is the Number of rows .
Thank you

  0 Comments

Sign in to comment.