PERL: How do I get both sizes of a matrix?

Thread Tools Search this Thread
Top Forums Shell Programming and Scripting PERL: How do I get both sizes of a matrix?
# 1  
Old 09-26-2007
Bug PERL: How do I get both sizes of a matrix?

Hi everybody,

I have a matrix called @matrix dinamically built in PERL, so I don't know its exact sizes. It is a 2-dimensional matrix, so its elements are for example:


I know i can get the number of the rows of the matrix with the commands:

scalar @matrix
$n_rows = @matrix

but I don't know how to get the number of the colums of the matrix!
I tried several ways like:

scalar @matrix[0]
$n_cols = @matrix[0]

but they haven't worked.

Can someone help me please? Thank you in advance,

# 2  
Old 09-26-2007
Although it's valid only for a column 0. try
scalar @{$matrix[0]}
$n_cols = @{$matrix[0]}

# 3  
Old 09-26-2007
Great! It works! I just needed the {} brackets! Smilie Thank you so much kahuna
Login or Register to Ask a Question

Previous Thread | Next Thread

9 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Make Separated files from a single matrix - Perl

Hey Masters, Here is my input: fragmentID chromosome start end HEL25E TRIP1 r5GATC2L00037 chr2L 5301 6026 0.03 0.036 r5GATC2L00038 chr2L 6023 6882 -0.025 -0.041 r5GATC2L00040 chr2R 6921 7695 -0.031 0.005 r5GATC2L00042 chr2R 7715 8554 -0.006 -0.024 r5GATC2L00043 chr3L 8551 8798 0.042 0... (4 Replies)
Discussion started by: @man
4 Replies

2. Shell Programming and Scripting

Randomization a matrix - perl / Shell

Hello all, I have a tricky question! (at least for me it is!). I'll try to explain it carefully here. Hope you can help me solving the whole or even parts of it! Here it is: I have a big input 0\1 table as a very simplified one is shown below: (The last row and column are the sum and... (0 Replies)
Discussion started by: @man
0 Replies

3. Shell Programming and Scripting

Perl- creating a matrix from a 3 column file

Dear all, I'm new in perl scripting and I'm trying to creating a matrix from a 3 column file sorting data in a particular manner. In the final matrix I need to have the first column "IDs" on the header of the columns and the second column values on the header of each row. And the value fo the... (2 Replies)
Discussion started by: gabrysfe
2 Replies

4. Programming

Matrix addition - Perl - PDL

Hi All, I have a question. I need to add 3 matrices of size 2000 x 2000. (i.e) 2000 rows and 2000 columns using Perl::PDL module. I used the following perl script #!/usr/bin/perl -w use strict; use warnings; use PDL; use PDL::Matrix; if ( @ARGV != 3 ) { die 'Two matrix files are... (1 Reply)
Discussion started by: Fredrick
1 Replies

5. Shell Programming and Scripting

3 column .csv --> correlation matrix; awk, perl?

Greetings, salutations. I have a 3 column csv file with ~13 million rows and I would like to generate a correlation matrix. Interestingly, you all previously provided a solution to the inverse of this problem. Thread title: "awk? adjacency matrix to adjacency list / correlation matrix to list"... (6 Replies)
Discussion started by: R3353
6 Replies

6. Shell Programming and Scripting

Invert Matrix of Data - Perl

I have columnar data in arrays perl, Example - @a = (1,2,3); @array1 = (A,B,C); @array2 = (D,E,F); @array3 = (I,R,T); I want the data to be formatted and printed as 1 A D I 2 B E F 3 C F T and so on... (8 Replies)
Discussion started by: dinjo_jo
8 Replies

7. Shell Programming and Scripting

diagonal matrix to square matrix

Hello, all! I am struggling with a short script to read a diagonal matrix for later retrieval. 1.000 0.234 0.435 0.123 0.012 0.102 0.325 0.412 0.087 0.098 1.000 0.111 0.412 0.115 0.058 0.091 0.190 0.045 0.058 1.000 0.205 0.542 0.335 0.054 0.117 0.203 0.125 1.000 0.587 0.159 0.357... (11 Replies)
Discussion started by: yifangt
11 Replies

8. Shell Programming and Scripting

Perl- matrix problem

A C G T - A 5 -4 -4 -4 -5 C -4 5 -4 -4 -5 G -4 -4 5 -4 -5 T -4 -4 -4 5 -5 - -5 -5 -5 -5 0 So lets say I have a matrix which looks something like (above). Its basically a scoring matrix. the numbers are... (2 Replies)
Discussion started by: aj05
2 Replies

9. Shell Programming and Scripting

PERL: How do i print an associative matrix?

Hello guys, I have in PERL an associative 2-dimensional array, called matrix. The array (actually the matrix) is made up like this matrix = x; matrix = y; matrix = w; matrix = z; ... but the names a, b, c, d are set just at runtime. The question is: how can i get all the keys of... (2 Replies)
Discussion started by:
2 Replies
Login or Register to Ask a Question