LI-COR LI-6400, Руководство пользователя

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Programming with LPL
Functions
Using the LI-6400 22-13
in functions of LPL, as well as functions that you may write, expect to find
certain types of objects on the stack. These objects are consumed from the
stack, and others may be put back onto the stack.
LPL provides a number of commands that directly manipulate the stack, such
as
DROP (discards top stack item), SWAP (exchanges top two stack items),
and
ROT
(exchanges first and third stack items). Also, stack size (the number
of items that can be held at any one time on the stack) can be set. The default
size is 10 items.
Post-fix
The default syntax within a function is post-fix. This means that operations
are programmed in order of stack operation. To add two values together, we
would write
17.83 2.5 +
If we want to go further, and store the result in a variable named X , we would
have to put X Õs address on the stack, then do a store command. In LPL, we
would write
17.83 2.5 + &X =
The & operator prefixed onto a variable name literally means Òput the address
of this variable onto the stackÓ, rather than the value of this variable. Pictori-
ally, the stack operations might look like this:
Operation
The Stack
... 2 1
Stack is empty:
Push 17.83 17.83
Push 2.5 17.83 2.5
Do the + 20.33
Push address 20.33 9057:0018
Do the =