select all rows (resp. columns) out of matrix

Ali Çehreli acehreli at yahoo.com
Thu Nov 14 14:26:03 PST 2013


On 11/14/2013 02:18 PM, TheFlyingFiddle wrote:
> On Thursday, 14 November 2013 at 22:06:28 UTC, seany wrote:
>> How do I access All rows (resp. columns ) of a Matrix /
>> multidimensional array?
>>
>> In scilab, you write array_var(:,row_index), colon meaning all
>> columns, at that particular row given by row index will be selected.
>>
>> can you, forexample, in D, write, array_var[0][] to select all
>> elements (columns, in this case i believe?) of array_var[0] ?
>
> unittest
> {
>    int[][] matrix = new int[][](n,m);
>
>    //Getting a collumn is simple.
>    int[] collumn0 = matrix[0];
>
>    //Getting a row is trickier
>    int[] row0;
>
>    //Loop over all collumns
>    foreach(i; matrix) {
>      row0 ~= matrix[i][0];
>    }
> }
>
>

transversal() is useful too: :)

   http://dlang.org/phobos/std_range.html#transversal

Ali



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