Python Coding

[Thomas Klemm]

You can use this Python to RPN - source code converter to translate your Python code for the HP-42S.

However, I had to adjust it a little bit to make it work:

Code:

LBL("Profit on Pricing")

p = 100 # Constant use for percentage

CST = PROMPT("Enter Cost  : ")
SEL = PROMPT("Enter Price : ")
MUP = PROMPT("Enter Markup: ")
MAR = PROMPT("Enter Margin: ")

if CST and SEL != 0: # if both true
   MAR = p * (SEL - CST) / SEL
   MUP = p * (SEL - CST) / CST

if MAR == 0: # if true compute Margin
   MAR = MUP / (1 + MUP / p)

# constant to plug into remaining formulas
q = 1 - MAR / p

if MUP == 0: # if true compute Markup
   MUP = MAR / q

if CST == 0: # if true compute Cost
   CST = SEL * q

if SEL == 0: # if true compute Price
   SEL = CST / q

print("==================")        
print("Cost   = " "%1.2f"%(CST))
print("Price  = " "%1.2f"%(SEL))
print("Markup = " "%1.1f"%(MUP)), ("%")
print("Margin = " "%1.1f"%(MAR)), ("%")
print("==================")
print("Profit = " "%1.2f"%(SEL - CST))
print("==========================================")

Some of the generated code can be simplified a bit.
For instance the following snippet:

Code:

if MAR == 0: # if true compute Margin
   MAR = MUP / (1 + MUP / p)

… is translated to:

Code:

RCL "MAR"       // MAR
0
XEQ 72          // compare, return bool
X≠0?            // if true?
GTO 02          // if body
GTO 03          // resume
LBL 02          // if body
RCL "MUP"       // MUP
1
RCL "MUP"       // MUP
RCL 00          // p
/
+
/
STO "MAR"       // MAR 
LBL 03          // resume

But we can use instead:

Code:

RCL "MAR"       // MAR
X≠0?            // if set?
GTO 03          // resume
RCL "MUP"       // MUP
1
RCL "MUP"       // MUP
RCL 00          // p
/
+
/
STO "MAR"       // MAR 
LBL 03          // resume

However the generated code to print the results doesn't appear to work.

Still I hope that you have fun with Python and your programs!