why is the script not working?

[greenflame]

I am trying to make a function that returns a smaller matrix from a
bigger one. For example, if the inputed matrix is:

test = [
[2 2 5 2 5],
[5 7 7 2 7],
[3 8 3 0 4],
[9 3 8 4 9]];

and the coords array is: [2,2,4,4]

then it should return:

output = [
[7 7 2],
[8 3 0],
[3 8 4]];

The script is located at: ali.freezope.org/submatrix text

It says the error is at line 133. It says: object expected. I dont see
why there is no object.

[RobG]

greenflame wrote:

I am trying to make a function that returns a smaller matrix from a
bigger one. For example, if the inputed matrix is:

test = [
[2 2 5 2 5],
[5 7 7 2 7],
[3 8 3 0 4],
[9 3 8 4 9]];

and the coords array is: [2,2,4,4]

then it should return:

output = [
[7 7 2],
[8 3 0],
[3 8 4]];

The script is located at: ali.freezope.org/submatrix text
Broken link :-(

Post links thusly:

<URL:http://mydomain.com/mypath/myfile.html>

The following is based on a presumption of what I expect you are doing.

You appear to be looking for row index 2 to 4 and column index 2 to 4,
*but* your test matrix does not have a row index 4 (it has four rows of
index 0-3).

Your function call seems to have the syntax:

subArray ( matrix, from_row, from_column, to_row, to_column )

So here is a function that does what you want:

function subArray( X, a, b, c, d ){
var Y = [];
for ( var i=0; i+a <= c; i++ ){
Y[i] = [];
for ( var j=0; j+b <= d; j++ ){
Y[i][j] = X[i+a][j+b];
}
}
return Y;
}

I think a more obvious syntax would be:

subArray ( matrix, from_row, to_row, from_column, to_column )

e.g.

var z = subArray( X, 2, 4, 2, 4 );

and the function becomes:

function subArray( X, a, b, c, d ){
var Y = [];
for ( var i=0; i+a <= b; i++ ){
Y[i] = [];
for ( var j=0; j+c <= d; j++ ){
Y[i][j] = X[i+a][j+c];
}
}
return Y;
}

It says the error is at line 133. It says: object expected. I dont see
why there is no object.

Post a working link and we'll see. :-)
--
Rob

[greenflame]

OK. I will try the suggestions. Also the fixed like is:
ali.freezope.org/submatrix test