columnPermute -- permute some columns

• Usage:

  columnPermute(m,i,{...})

• Inputs:
  • m, a mutable matrix
  • i, an integer, starting column
  • a list of integers, denoting a permutation of 0..d, for some number d
• Consequences:

  • If the permutation is {p0,p1,...,pd}, then m is modified so that the i+j column becomes the i+pj column of the original matrix, for j=0..d

i1 : m = mutableMatrix map(ZZ^5,ZZ^6, (i,j) -> 100*i+j)

o1 = | 0   1   2   3   4   5   |
     | 100 101 102 103 104 105 |
     | 200 201 202 203 204 205 |
     | 300 301 302 303 304 305 |
     | 400 401 402 403 404 405 |

o1 : MutableMatrix

i2 : columnPermute(m,1,{2,0,1})

o2 = | 0   3   1   2   4   5   |
     | 100 103 101 102 104 105 |
     | 200 203 201 202 204 205 |
     | 300 303 301 302 304 305 |
     | 400 403 401 402 404 405 |

o2 : MutableMatrix