Classic RPN Stack Operations
Starting Stack:
T: d
Z: c
Y: b
X: a
OVER: Copies b to the Z and X stacks, while leaving a in the Y stack. c is pushed to the T stack.
T: d
-> c
Z: c -> b
Y: b -> a
X:
a -> b
RPN Keystrokes:
x<>y
ENTER
R↓
x<>y
R↑
ROT: Rotate Up. The contents of the T stack is untouched.
T: d ->
d
Z: c -> b
Y: b -> a
X:
a -> c
RPN Keystrokes:
R↓
R↓
x<>y
R↓
UNROT: Rotate
Down. The contents of the T stack is untouched.
T:
d -> d
Z: c -> a
Y: b ->
c
X: a -> b
RPN Keystrokes:
R↑
X<>Y
R↑
R↑
DROP: Drops the contents of the X stack. It is named DROPX on the R47. d is copied onto the Z stack.
T: d ->
d
Z: c -> d
Y: b -> b
X:
a -> c
RPN Keystrokes:
CL
x
+
NIP: Drops the
contents of the Y stack. It is named DROPY on the R47.
d is copied onto the Z stack.
T: d
-> d
Z: c -> d
Y: b -> c
X:
a -> a
RPN Keystrokes:
x<>y
CL
x
+
DROP2: Deletes a and b from the X and Y stacks, respectively, and replaces them with c and d.
T: d ->
0
Z: c -> 0
Y: b -> d
X:
a -> c
RPN Keystrokes:
R↓
CL
x
ENTER
R↓
R↓
DUP2: Duplicates a and b on to the Z and T stacks, respectively.
(Ball, John A. Algorithms for RPN Calculators. John Wiley & Sons, Inc. New York, NY. 1978)
T: d ->
b
Z: c -> a
Y: b -> b
X:
a -> a
RPN Keystrokes:
ENTER
ENTER
CL
x
-
R↓
x<>y
R↓
Eddie
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