Initial commit

maths

@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+
+import sys
+import operator
+from functools import reduce as fold
+import argparse
+
+
+mul = lambda xs: fold(operator.mul, xs)
+operators = {
+	"sum": sum, "+": sum,
+	"mul": mul, "*": mul,
+	"max": max,
+	"min": min
+}
+default_operator = "+"
+
+
+parser = argparse.ArgumentParser(description="Do maths on stdin")
+parser.add_argument(
+	"operator",
+	metavar="op",
+	nargs='?',
+	choices=list(operators.keys()),
+	default=default_operator,
+	help="Action to take (one of: {}; default: {})".format(
+		", ".join(operators.keys()),
+		default_operator
+	)
+)
+parser.add_argument(
+	"--int",
+	dest="datatype",
+	action="store_const",
+	const=(int, "integer"),
+	default=(float, "decimal number"),
+	help="use integers (default: float)"
+)
+args = parser.parse_args()
+
+
+op = operators[args.operator]
+parse_func, datatype_name = args.datatype
+
+data = []
+for i, line in enumerate(sys.stdin, start=1):
+	if line == "\n":
+		continue
+	try:
+		data.append(parse_func(line))
+	except ValueError:
+		print("Line {} could not be interpreted as a {}: {:r}".format(i, datatype_name, line.rstrip("\n")))
+		sys.exit(3)
+
+print(op(data))