The most straightforward way
to extract the stored value from a variable is to use the s
r (calc-recall) command. This command prompts
for a variable name (similarly to calc-store), looks
up the value of the specified variable, and pushes that value
onto the stack. It is an error to try to recall a void
variable.
It is also possible to recall the value from a variable by evaluating a formula containing that variable. For example, ' a <RET> = is the same as s r a <RET> except that if the variable is void, the former will simply leave the formula ‘a’ on the stack whereas the latter will produce an error message.
The r prefix may be followed by a digit, so that r 9 is equivalent to s r 9.