Matrix operations  WP 34S Message #1 Posted by Paul Dale on 6 Oct 2011, 5:03 a.m.
The matrix support operations are slowly of converging. There might be a few changes from here but most are now finalised.
I've swapped out the LU decomposition wrapper for the row operations. Does anyone want the explicit LU decomposition? Speak now or it is invisible forever  I'm not aware of a use of the LU decomposition apart from finding determinants, inverses and solving linear equations (all of which we have).
I've updated the matrix multiply so that the result can replace or overlap the source matrices. This means you can square a 10x10 matrix safely. However, I'm at a loss as to how to do something similar for the generalised addition A = A + k B. Any suggestions? Should I split the constant multiple of a matrix from the matrix addition?
The loop index generating functions will probably stay as they are as will the register to I, J index and the reverse.
The matrix row operations are likely to stay but this is not yet not definite. For RREF they are useful. Beyond that???
The row and column query count functions might disappear... Anyone need a nicely behaved version of these instead of a user code version? The difference is lastX and the stack damage. These function are not much more than multiply by 100 and IP.
As for creating & initialising a matrix  identity & zero are in user code now but they are mostly well behaved  they damage L & nothing else. Marcus has done a matrix editor which should cover the rest pretty well.
What about a matrix copy? User code with stack damage or C and well behaved?
 Pauli
 Pauli
