simple python script that requires no installation or setting up. Just run it to get a command line that executes math calculations like "cos(2.4*pi)". I tried to emulate the matlab command line, but with faster start up.

Console_Calculator.py

from math import *
while True:
    inputText = input('>> ')
    try:
        Result = eval(inputText)
        print(Result)
    except:
        try:
            exec(inputText)
            print('executed')
        except:
            print('error')