Maple Tutor
Part 5: What Maple
remembers
- Create a new region and type
x:=15;
Then press the SHIFT and RETURN keys together. This gives you a
new line within the region and does not evaluate the current line. Now type
7.3/2.5;
Then press RETURN to evaluate both lines.
- Go back into the region, delete
the line
x:=15;
and press RETURN. In the new region, enter
x;
Notice that Maple still remembers that x has been
assigned the value 15 -- even though that line no longer appears in
the worksheet.
We have come to the second
important fact about Maple. (Ending a computation line with a semicolon
or colon was the first.) Maple remembers what has been entered
in the order it was entered.
- It doesn't matter what is currently
in the worksheet, nor the order things appear in that worksheet. You may have
assigned a value, erased the assigning command line, and forgotten about it.
But Maple remembers. If you use x later, assuming it is an unassigned
variable, strange things will happen.
- If variables are assigned
new values, formulas using those variables acquire new values as well.
Finally a third important fact about
Maple: If you save a Maple file without removing the output, then
reload it later, it will look the same as when you saved it. But Maple
will not remember any of the displayed commands. All of those commands must
be reentered before you are again in the same state as when you saved and closed
the file.
