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Matrix _ List -- select columns

Synopsis

Usage:
f_cols
Operator: _
Inputs:
- f, a matrix, a matrix between free modules
- cols, a list, a list of integers denoting the choice of columns
Outputs:
- a matrix, the submatrix of f corresponding to the columns cols.

Description

This is the same as calling submatrix(f,cols).

i1 : R = QQ[a..f];

i2 : p = matrix {{a,b,c},{d,e,f}}

o2 = | a b c |
     | d e f |

             2       3
o2 : Matrix R  <--- R

i3 : p_{1}

o3 = | b |
     | e |

             2       1
o3 : Matrix R  <--- R

i4 : p_{1,2,0}

o4 = | b c a |
     | e f d |

             2       3
o4 : Matrix R  <--- R

See also

submatrix
Matrix ^ List -- select rows