Added function to convert from decimal to another base

conversions/decimal_to_any.py

@@ -0,0 +1,104 @@
+"""Convert a positive Decimal Number to Any Other Representation"""
+
+
+def decimal_to_any(num: int, base: int) -> str:
+
+    """
+        Convert a positive integer to another base as str.
+        >>> decimal_to_any(0, 2)
+        '0'
+        >>> decimal_to_any(5, 4)
+        '11'
+        >>> decimal_to_any(20, 3)
+        '202'
+        >>> decimal_to_any(58, 16)
+        '3A'
+        >>> decimal_to_any(243, 17)
+        'E5'
+        >>> decimal_to_any(34923, 36)
+        'QY3'
+        >>> decimal_to_any(10, 11)
+        'A'
+        >>> decimal_to_any(16, 16)
+        '10'
+        >>> decimal_to_any(36, 36)
+        '10'
+        >>> # negatives will error
+        >>> decimal_to_any(-45, 8)  # doctest: +ELLIPSIS
+        Traceback (most recent call last):
+        ...
+        ValueError: parameter must be positive int
+        >>> # floats will error
+        >>> decimal_to_any(34.4, 6) # doctest: +ELLIPSIS
+        Traceback (most recent call last):
+        ...
+        TypeError: int() can't convert non-string with explicit base
+        >>> # a float base will error
+        >>> decimal_to_any(5, 2.5) # doctest: +ELLIPSIS
+        Traceback (most recent call last):
+        ...
+        TypeError: 'float' object cannot be interpreted as an integer
+        >>> # a str base will error
+        >>> decimal_to_any(10, '16') # doctest: +ELLIPSIS
+        Traceback (most recent call last):
+        ...
+        TypeError: 'str' object cannot be interpreted as an integer
+        >>> # a base less than 2 will error
+        >>> decimal_to_any(7, 0) # doctest: +ELLIPSIS
+        Traceback (most recent call last):
+        ...
+        ValueError: base must be >= 2
+        >>> # a base greater than 36 will error
+        >>> decimal_to_any(34, 37) # doctest: +ELLIPSIS
+        Traceback (most recent call last):
+        ...
+        ValueError: base must be <= 36
+    """
+    if isinstance(num, float):
+        raise TypeError("int() can't convert non-string with explicit base")
+    if num < 0:
+        raise ValueError("parameter must be positive int")
+    if isinstance(base, str):
+        raise TypeError("'str' object cannot be interpreted as an integer")
+    if isinstance(base, float):
+        raise TypeError("'float' object cannot be interpreted as an integer")
+    if base in (0, 1):
+        raise ValueError("base must be >= 2")
+    if base > 36:
+        raise ValueError("base must be <= 36")
+
+    ALPHABET_VALUES = {'10': 'A', '11': 'B', '12': 'C', '13': 'D', '14': 'E', '15': 'F', '16': 'G', '17': 'H',
+                       '18': 'I', '19': 'J', '20': 'K', '21': 'L', '22': 'M', '23': 'N', '24': 'O', '25': 'P',
+                       '26': 'Q', '27': 'R', '28': 'S', '29': 'T', '30': 'U', '31': 'V', '32': 'W', '33': 'X',
+                       '34': 'Y', '35': 'Z'}
+    new_value = ""
+    mod = 0
+    div = 0
+    while div != 1:
+        div, mod = divmod(num, base)
+        if base >= 11 and 9 < mod < 36:
+            actual_value = ALPHABET_VALUES[str(mod)]
+            mod = actual_value
+        new_value += str(mod)
+        div = num // base
+        num = div
+        if div == 0:
+            return str(new_value[::-1])
+        elif div == 1:
+            new_value += str(div)
+            return str(new_value[::-1])
+
+    return new_value[::-1]
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()
+
+    for base in range(2, 37):
+        for num in range(1000):
+            assert int(decimal_to_any(num, base), base) == num, (
+                num, base, decimal_to_any(num, base),
+                int(decimal_to_any(num, base), base)
+                )