eval() Function in Python Example
Python3
print(eval('1+2'))print(eval("sum([1, 2, 3, 4])")) |
Output:
310
Simple Demonstration of eval() works
Let us explore it with the help of a simple Python program. function_creator is a function that evaluates the mathematical functions created by the user. Let us analyze the code a bit:
- The above function takes any expression in variable x as input.
- Then the user has to enter a value of x.
- Finally, we evaluate the Python expression using the eval() built-in function by passing the expr as an argument.
Python3
def function_creator(): # expression to be evaluated expr = input("Enter the function(in terms of x):") # variable used in expression x = int(input("Enter the value of x:")) # evaluating expression y = eval(expr) # printing evaluated result print("y =", y)if __name__ == "__main__": function_creator() |
Output:
Enter the function(in terms of x):x*(x+1)*(x+2)
Enter the value of x:3
y = 60
eval in Python
Python eval() function parse the expression argument and evaluate it as a Python expression and runs Python expression (code) within the program.