help mata tostack()
help mata enter()
help mata swapst()
help mata rotst()
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Title

    Commands to manipulate the internal stack set up by rpnfcn()


Syntax

                Command name      Argument

                &tostack()        x

                &enter()          NULL

                &swapst()         NULL

                &rotst()          NULL


Description

    These functions are used to place matrices into the appropriate places in
    the stack used by rpnfcn().  &tostack() places the matrix x in a new top
    element of the stack. &enter() copies the current top element of the
    stack to a new top element in the stack. &swapst() swaps the two top
    elements of the stack. &rotst() rotates the stack one step down, meaning
    that the bottom-most element becomes the top element, while all others
    are shifted one step down.

Remarks

    The commands &tostack() and &enter() both copies the indicated matrix,
    and for very large matrices the user must thus ensure that Stata has
    sufficient memory to execute the command. The commands &swapst() and
    &rotst() on the other hand do not move or copy matrices as such, but
    rather rearranges their labels (the pointers in the stack) so as to
    create the desired effect.


Source code

    rpnstackfcn.mata

Author

    Henrik Støvring, Research Unit of General Practice, University of
    Southern Denmark.  Please email hstovring@health.sdu.dk if you have
    comments, questions or observe any problems.


Also see

    Manual:  [M] Mata Reference Manual

    Online:  help for [M-0] mata,  Evaluation of algorithm matrix using RPN,
             RPN binary operators, RPN distribution functions, RPN functions
             for integration