RPN Mode: Possible to use advanced matrix operations?

[toml_12953]

(05-07-2017 02:37 PM)johan162 Wrote:  Thanks for your reply but I'm quite aware of RPN and stack, thats what I have been using for the last 30 years:-)

Calculating the determinant is one of the operations that actually happen to work (and is not in the second level menu) work as expected (i.e. put the mat on the stack and execute the operation). However, My question was regarding what HP consider advanced operations such as finding the Eigenvalues/Eigenvectors

If you put the matrix on the stack and try to execute, say, "EIGENVAL()" (menu 7->6->1) then that does not operate on the stack. However, if you try to copy the matrix from the stack as an operand to "EIGENVAL()" or use a matrix varible all you get is "Syntax error" _as long as you are in RPN mode_

So, as long as you are in the "Home" calculator view and have it set to RPN-mode I cannot for my life get things like the eigenvalues to work. Of course if you switch back to "Algebraic" (or Textbook) then operation like "EIGENVAL()" works as expected.

My guess is that since these operations are implemented in the CAS environment (even if you can use them from the Home) that will never work in the RPN mode.

Unfortunately this really makes the RPN mode very limited if that only supports a limited set of operation that on the surface seems inconsistent. For example, why should calculating the determinant work but not finding eigenvalues? I of course appreciate the difference in complexity in implementing these operations but from a high level point of view there is no real difference - just an inconsistency.

In the long run this really makes it necessary to have the calc in algebraic/textbook mode to avoid inconsistencies -ar at least as long as you expect to do heavy matrix calculations (which I happen to do a lot..)

EIGENVAL(1) works for me when the matrix is on the stack. It works the same as DET(), or any function.

Tom L