HP 33s - Manual (Page 317)

ALG: Summary C–7
You can press — or ˜ (or  and | ) to review the entire contents
of the stack and recall them.
However, in normal operation in ALG mode, the stack in ALG mode differs from
the one in RPN mode. (Because when you press
‘ , the result is not placed
into X1, X2 etc.) Only after evaluating equations, programs, or integrating
equations
, the values of the four registers will be the same as in RPN mode.
Coordinate Conversions
To convert between rectangular and polar coordinates:
1. Enter the coordinates (in rectangular or polar form) that you want to convert. In
ALG mode, the order is y
[ x or
θ [ r .
2. Execute the conversion you want: press { r (rectangular–to–polar) or
| s (polar–to–rectangular). The converted coordinates occupy the X–
and Y–registers.
3. The resulting display (the X–register) shows either r (polar result) or x
(rectangular result). Press
š to see
θ
or y.
Example:
If x = 5, y = 30, what are r, θ ?
Keys: Display: Description:
Ÿ {}  Sets Degrees mode.
30 [ 5 { r

8´
θ8T
T/
) 
Calculates hypotenuse (r).
š

8´
θ8T
θ/
)

Displays θ .
If r = 25, θ = 56, what are x, y ?
Keys: Display: Description:
Ÿ {}  Sets Degrees mode.
56 [ 25 | s
 8´¸8º
%/)
 Calculates x.