matrices.py

   1 from cvxopt import matrix, spmatrix
   2
   3 def append_col(A,b):
   4     """
   5     Append the column ``b`` to the right side of the matrix ``A``.
   6     """
   7     return matrix([A.trans(),b.trans()]).trans()
   8
   9 def append_cols(cols):
  10     """
  11     Append a bunch of columns together, left to right.
  12     """
  13     if len(cols) == 0:
  14         return cols
  15
  16     result = cols[0]
  17     del(cols[0])
  18     for column in cols:
  19         result = append_col(result, column)
  20
  21     return result
  22
  23
  24 def append_row(A,b):
  25     """
  26     Append the row ``b`` to the bottom of the matrix ``A``.
  27     """
  28     return matrix([A,b])
  29
  30 def identity(n):
  31     """
  32     Return the ``n``-by-``n`` identity matrix.
  33     """
  34     return spmatrix(1,range(n),range(n))