Add signum function

maths/signum.py

@@ -0,0 +1,35 @@
+"""Signum function"""
+
+def signum(num):
+    """
+    Applies signum function on the number
+
+    >>> signum(-10)
+    -1
+    >>> signum(10)
+    1
+    >>> signum(0)
+    0
+    """
+    if num < 0:
+        return -1
+    elif num > 0:
+        return 1
+    else:
+        return 0
+
+
+def test_signum():
+    """
+    Tests the signum function
+    """
+    assert(signum(5) == 1)
+    assert(signum(-5) == -1)
+    assert(signum(0) == 0)
+
+
+if __name__ == "__main__":
+    print(signum(12))
+    print(signum(-12))
+    print(signum(0))
+