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README.md

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+```
+This is an RPN (Reverse Polish Notation) calculator program. This works by pushing numbers to a stack, and then completing operations on the pushed numbers in the order that they were added to the stack.
+
+Example: 4 [enter] 3 [enter] * [enter]
+Will display 12 on the Current Stack (i.e. 4 * 3 = 12)
+
+Many more math functions are available:
+
+[Command]            [Function]
+q                    quit calculator (ctrl-c also works)
++                    add the last two numbers on the stack
+-                    subtract the last two numbers on the stack
+* or x               multiply the last two numbers on the stack
+/                    divide the last two numbers on the stack
+%                    output the remainder of the division of the last two numbers on the stack (modulus)
+clear or c           clear the stack of all values
+del or d             remove the last number pushed to the stack (this can be repeated multiple times)
+floor                take the last two numbers from the stack, and push the lower number back onto the stack
+ceil                 take the last two numbers from the stack, and push the higher number back onto the stack
+round                round the last number on the stack (follows conventional rules, 0.5 rounds up)
+abs                  change the last number on the stack to it's absolute value
+pow                  raise the number on the stack prior to the last input to the power of the last number input
+                         Example: 3 [enter] 2 [enter] pow [enter] Output: 9
+sqrt or v            change the last number on the stack to it's square root
+cbrt or v3           change the last number on the stack to it's cube root
+ln                   change the last number on the stack to it's natural log
+log                  change the last number on the stack to it's base10 log
+sin                  change the last number on the stack to it's sine value (radians)
+asin, sinh               the same thing, but arc and hyperbolic instead
+cos                  change the last number on the stack to it's cosine value (radians)
+acos, cosh               the same thing, but arc and hyperbolic instead
+tan                  change the last number on the stack to it's tangent value (radians)
+atan, tanh               the same thing, but arc and hyperbolic instead
+me                   pushes the machine epsilon value onto the stack
+pi                   pushes pi onto the stack
+tau                  pushes tau on to the stack
+help or ?            print this help text
+```