T

 

 

 

 

 

 

 

 

 

Z

 

 

 

 

 

 

 

 

 

Y

 

 

1

 

1

 

1

 

1

1 X

1

1

2

2

C

0

3

3

1

2

 

3

 

4

 

5

 

1.Lifts the stack

2.Lifts the stack and replicates the X–register.

3.Overwrites the X–register.4.Clears x by overwriting it with zero.5.Overwrites x (replaces the zero.)

The LAST X Register

The LAST X register is a companion to the stack: it holds the number that was in the X–register before the last numeric function was executed. (A numeric function is an operation that produces a result from another number or numbers, such as .)

Pressing returns this value into the X–register.This ability to retrieve the "last x" has two main uses:1.Correcting errors.2.Reusing a number in a calculation.

See appendix B for a comprehensive list of the functions that save x in the LAST X register.