External calculation for Gedit

calculate

#!/usr/bin/env python3
# [Gedit Tool]
# Name=Calculate
# Input=selection
# Output=replace-selection
# Applicability=always
# Save-files=nothing
# Shortcut=<Primary><Alt>c
# Languages=


import re
import sys
import sympy

input_string = sys.stdin.read()
output = [input_string]
try:
    evaluation = sympy.sympify(input_string, rational=True, evaluate=True)
    numerical_evaluation = evaluation.evalf(15)
except sympy.SympifyError:
    output.extend(["=", "?"])
else:
    e = str(evaluation)
    if evaluation.is_integer or re.sub(r"\s+", "", input_string) != e:
        output.extend(["=", e])
    if evaluation.is_zero and e != "0":
        output.extend(["=", "0"])
    n = re.sub(r"\.0+$", "", re.sub(r"(\d+\.\d+?)0+($|e.*)", r"\1\2",
                                    str(numerical_evaluation)))
    if not evaluation.is_integer and n not in output:
        if sympy.sympify(f"{e}-{n}", rational=True, evaluate=True).is_zero:
            output.extend(["=", n])
        else:
            output.extend(["≈", n])
finally:
    print(" ".join(output), end="")