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Version 23

2016-02-17, 16:50:02

Version 24

2016-02-18, 16:57:58

Idiom #26 Create a 2-dimensional array

Declare and initialize a matrix x having m rows and n columns, containing real numbers.

Idiom #26 Create a 2-dimensional array

Declare and initialize a matrix x having m rows and n columns, containing real numbers.

Code 
X : array (1 .. M, 1 .. N) of Float := (others => (others => 1.0));
Code 
X = [{R * 1.0, C * 1.0} || R <- lists:seq(1, M), C <- lists:seq(1, N)].
Code 
X = [{R * 1.0, C * 1.0} || R <- lists:seq(1, M), C <- lists:seq(1, N)].
Comments bubble
You don't declare and initialize in Erlang. This is the closest thing.
Comments bubble
You don't declare and initialize in Erlang. This is the closest thing.
Doc URL
http://learnyousomeerlang.com/starting-out-for-real#list-comprehensions
Doc URL
http://learnyousomeerlang.com/starting-out-for-real#list-comprehensions
Demo URL
http://tryerl.seriyps.ru/#id=02f3
Demo URL
http://tryerl.seriyps.ru/#id=02f3
Imports 
#include <stdlib.h>
Imports 
#include <stdlib.h>
Code 
double **x=malloc(m*sizeof(double *));
int i;
for(i=0;i<m;i++)
{
	x[i]=malloc(n*sizeof(double));
}
Code 
double **x=malloc(m*sizeof(double *));
int i;
for(i=0;i<m;i++)
{
	x[i]=malloc(n*sizeof(double));
}
Comments bubble
This uses dynamic allocation.
Comments bubble
This uses dynamic allocation.
Code 
const m, n = 2, 3
var x [m][n]float64
Code 
const m, n = 2, 3
var x [m][n]float64
Comments bubble
m, n must be constant for this syntax to be valid.
Here x is of type [2][3]float64, it is not a slice.
Comments bubble
m, n must be constant for this syntax to be valid.
Here x is of type [2][3]float64, it is not a slice.
Demo URL
http://play.golang.org/p/cAqJGf9q1y
Demo URL
http://play.golang.org/p/cAqJGf9q1y