(34S) Integration (using the double-exponential method)

[Paul Dale]

(03-27-2017 05:42 PM)emece67 Wrote:  Keeps ABCD untouched

It is not possible to use A..D-> and ->A..D to preserve the A-D registers across a call to user code. These commands stash the register values at a fixed location in volatile RAM which will be lost under some circumstances.

It will also break with nested integrals or with mixed solve and integrate.

The only way to preserve the A-D registers is to allocate four additional local registers for the purpose.


The A..D-> and ->A..D commands are left from when I implemented solve without the benefit of local registers and had to squeeze everything into a very limited number of special XROM registers. I needed more temporary space so I added these two commands. Like several other specials for XROM, they are extremely specific to my purpose at the time and come with major caveats.


- Pauli