Merge pull request #282 from realpython/python-absolute-value

Python abs() - Supplemental Materials

Author: bzaczynski

python-absolute-value/README.md

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+# How to Find an Absolute Value in Python
+
+Supplemental materials for the [tutorial on absolute values](https://realpython.com/python-absolute-value/) hosted on Real Python.

python-absolute-value/sample_code.py

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+import math
+from decimal import Decimal
+from fractions import Fraction
+from math import sqrt
+
+
+class VectorBound:
+    def __init__(self, *coordinates):
+        self.coordinates = coordinates
+
+    def __abs__(self):
+        origin = [0] * len(self.coordinates)
+        return math.dist(origin, self.coordinates)
+
+
+class VectorFree:
+    def __init__(self, *coordinates):
+        self.coordinates = coordinates
+
+    def __abs__(self):
+        return math.hypot(*self.coordinates)
+
+
+def absolute_value_piecewise(x):
+    if x >= 0:
+        return x
+    else:
+        return -x
+
+
+def absolute_value_piecewise_conditional_expression(x):
+    return x if x >= 0 else -x
+
+
+def absolute_value_algebraic(x):
+    return sqrt(pow(x, 2))
+
+
+def absolute_value_algebraic_exponents(x):
+    return (x**2) ** 0.5
+
+
+def absolute_value_silly(x):
+    return float(str(x).replace("-", ""))
+
+
+if __name__ == "__main__":
+    print(f"{absolute_value_piecewise(-12) = }")
+    print(f"{absolute_value_piecewise_conditional_expression(-12) = }")
+    print(f"{absolute_value_algebraic(-12) = }")
+    print(f"{absolute_value_algebraic_exponents(-12) = }")
+    print(f"{absolute_value_silly(-12) = }")
+
+    print(f"{abs(-12) = }")
+    print(f"{abs(-12.0) = }")
+    print(f"{abs(complex(3, 2)) = }")
+    print(f"{abs(Fraction('-3/4')) = }")
+    print(f"{abs(Decimal('-0.75')) = }")
+
+    print(f"{abs(VectorBound(0.42, 1.5, 0.87)) = }")
+    print(f"{abs(VectorFree(0.42, 1.5, 0.87)) = }")