NeoCal User Guide
Working Registers
NeoCal uses several registers for performing calculations with the
most commonly used labeled x, y, and last x.
The x register contains the number shown in the display, while
the y register is paired with the x register when two
values are required for a calculation or returned from a calculation.
The last x register stores the value of the x register
before the last numeric operation was performed.
As an example, let's add the numbers 12 and 15:
- Pressing
places the
number 12 in the x register.
- Pressing
copies the value stored in the
x register into the y register.
- Pressing
stores the
number 15 in the x register.
- Pressing
adds the numbers in the x
and y registers and places the result in the x
register (which is shown on the display). The y register
contains the value it contained before we started this calculation.
The last x register contains the number 15.
Many keys are labeled with x (
) or x and y
(
) referring to the x and y
registers. The general rule is to enter the y value first,
then the x value. Also,
- Pressing the
button will exchange or swap
the values stored in the x and y registers. This is
often used when two values are returned from an operation and you
want to view the additional value.
- Pressing the
button recalls the value
stored in the last x register into the x register.
This allows a number to be used repeatedly without having to
re-enter it.
The RPN input method also recognizes two more registers, z
and t, which are discussed in RPN Tutorial.