HP HP-28S - Page 265

As an example, if ~DAT is the n x 2 matrix
then ~COV will contain the covariance matrix
1 :
Program
F.: C u::
DUP
TF.:t·l
:;~lAP l
Arguments
':l;CO\} , STO
o PRED'.} DROP
I ENTER I
~ SUMS ISTOI
Results
1 :
Comments
Begin the program.
Recall
the contents of the n x m
statistics matrix ~DAT.
Make a copy.
Transpose
the matrix. The result
is
an m x n matrix.
Multiply
the matrices to produce
the m x m covariance matrix.
(Without
swapping the matrices,
the product would be an n x n
matrix.)
Store
the covariance matrix in a
variable
~COv.
Make sure ~PAR exists.
End
the program.
Put the program on the stack.
Store
the program as SUMS.
264 28: Programming Examples