Matrix Calculator using Numpy

matrix.py

# matrix calculator
import numpy as np

if __name__ == "__main__":
	# select matrix dimemsion
	print("#### MATRIX CALCULATOR ####")
	print("Paper work: ")
	print("-- Separate row elements by spaces")
	print("-- Use x to end matrix input")
	print("-- Use only nxn matrices for non-arithmetic operations")
	print()
	op = int(input("Operation: arithmetic=0, determinant=1, inverse=2: "))

	if op == 0: # arithmetic ops
		# matrix A
		print("matA: ")
		matA = []
		ar = input() # A row
		while ar != "x":
			r = list(map(int, ar.split()))
			matA.append(r)
			ar = input()

		# operator
		print("Operator: +, -, *")
		optr = input()

		# matrix B
		print("matB: ")
		matB = []
		br = input() # B row
		while br != "x":
			r = list(map(int, br.split()))
			matB.append(r)
			br = input()

		try:
			np_matA = np.matrix(matA)
			np_matB = np.matrix(matB)

			# operations
			if optr == '+':
				result = np_matA + np_matB
			elif optr == '-':
				result = np_matA - np_matB
			elif optr == '*':
				result = np_matA * np_matB
			else:
				print("Invalid operator!")
		except:
			print("Error: Invalid/unconformable matrix/matrices!")
			raise

		# result
		print("Ans: ")
		[print(str(r)[1:-1]) for r in result]

	else:
		# matrix
		print("mat: ")
		mat = []
		rw = input() # row
		while rw != "x":
			r = list(map(int, rw.split()))
			mat.append(r)
			rw = input()

		try:
			if op == 1: # determinant
				result = np.linalg.det(mat)
				print("Ans: ", result)
			elif op == 2: # inverse
				result = np.linalg.inv(mat)
				print("Ans: ")
				[print(str(r)[1:-1]) for r in result]
		except:
			print("Error: Invalid/unconformable matrix!")
			raise