list_astro

  read a series of lines consisting of 4 columns.  the columns
  represent the X,Y coordinate of a series of objects in first one
  coordinate frame, then in a second coordinate frame.  list_astro
  will return the linear transformation (and errors) from the first
  frame to the second frame in the form:

  X0 X1 X2 dX
  Y0 Y1 Y2 dY

  where

  X = X0 + X1*x + X2*y
  Y = Y0 + Y1*x + Y2*y

  and dX and dY are the errors in the output coordinate frame.