CSVWRITE Write Comma Separated Value (CSV) File

Section: Input/Ouput Functions


The csvwrite function writes a given matrix to a text file using comma separated value (CSV) notation. Note that you can create CSV files with arbitrary sized matrices, but that csvread has limits on line length. If you need to reliably read and write large matrices, use rawwrite and rawread respectively. The syntax for csvwrite is

where x is a numeric array. The contents of x are written to filename as comma-separated values. You can also specify a row and column offset to csvwrite to force csvwrite to write the matrix x starting at the specified location in the file. This syntax of the function is


where startrow and startcol are the offsets in zero-based indexing.


Here we create a simple matrix, and write it to a CSV file
--> x = [1,2,3;5,6,7]

x = 
 1 2 3 
 5 6 7 

--> csvwrite('csvwrite.csv',x)
--> csvread('csvwrite.csv')

ans = 
 1 2 3 
 5 6 7 

Next, we do the same with an offset.

--> csvwrite('csvwrite.csv',x,1,2)
--> csvread('csvwrite.csv')

ans = 
 0 0 0 0 
 0 1 2 3 
 0 5 6 7 

Note the extra zeros.