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Silviu Marian Udrescu 2020-04-25 21:17:45 -04:00 • committed by GitHub
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RPN_to_eq.py Normal file
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# Turns an RPN expression to normal mathematical notation
import numpy as np
def RPN_to_eq(expr):
variables = ["0","1","a","b","c","d","e","f","g","h","i","j","k","l","m","n","P"]
operations_1 = [">","<","~","\\","L","E","S","C","A","N","T","R","O","J"]
operations_2 = ["+","*","-","/"]
stack = np.array([])
for i in (expr):
if i in variables:
if i == "P":
stack = np.append(stack,"pi")
elif i == "0":
stack = np.append(stack,"0")
elif i == "1":
stack = np.append(stack,"1")
else:
stack = np.append(stack,"x" + str(ord(i)-97))
elif i in operations_2:
a1 = stack[-1]
a2 = stack[-2]
stack = np.delete(stack,-1)
stack = np.delete(stack,-1)
a = "("+a2+i+a1+")"
stack = np.append(stack,a)
elif i in operations_1:
a = stack[-1]
stack = np.delete(stack,-1)
if i==">":
a="("+a+"+1)"
stack = np.append(stack,a)
if i=="<":
a="("+a+"-1)"
stack = np.append(stack,a)
if i=="~":
a="(-"+a+")"
stack = np.append(stack,a)
if i=="\\":
a="("+a+")**(-1)"
stack = np.append(stack,a)
if i=="L":
a="log("+a+")"
stack = np.append(stack,a)
if i=="E":
a="exp("+a+")"
stack = np.append(stack,a)
if i=="S":
a="sin("+a+")"
stack = np.append(stack,a)
if i=="C":
a="cos("+a+")"
stack = np.append(stack,a)
if i=="A":
a="abs("+a+")"
stack = np.append(stack,a)
if i=="N":
a="asin("+a+")"
stack = np.append(stack,a)
if i=="T":
a="atan("+a+")"
stack = np.append(stack,a)
if i=="R":
a="sqrt("+a+")"
stack = np.append(stack,a)
if i=="O":
a="(2*("+a+"))"
stack = np.append(stack,a)
if i=="J":
a="(2*("+a+")+1)"
stack = np.append(stack,a)
return(stack[0])