Reference · Math

math.fabs

math.fabs(num) -> float

What it does

The absolute value, always as a float, as Python's math.fabs: math.fabs(-3) is 3.0. abs keeps an int an int and takes a decimal too; this one is for float arithmetic.

Examples

print(math.fabs(-3), math.fabs(3.5), math.fabs(-2.25))print(type_of(math.fabs(-3)), type_of(abs(-3)))

3.0 3.5 2.25float int

Edge cases

• -0.0 gives 0.0.
• Infinity gives infinity, and NaN stays NaN; neither is an error.
• An int beyond 2⁵³ loses precision on the way to a float, as any int to float conversion does.

print(math.fabs(-0.0), math.fabs(float("-inf")), math.fabs(float("nan")))print(math.fabs(-9007199254740993))

0.0 inf NaN9007199254740992.0

Errors

An argument that is not a number is a runtime error, not an error value. A decimal is refused with a hint to convert it with float; abs takes a decimal as it is.

print(math.fabs("x"))

line 1: `math.fabs` expects a number as argument 1, got str

print(math.fabs(dec("-1")))

line 1: `math.fabs` expects a number as argument 1, got dec (this works on floats: convert a dec with float(x))

Chaining

In a pipeline the number comes first. Differences become distances:

print(-2.5 | math.fabs)print([3, -1, 2] | map((x) => x - 2) | map(math.fabs))

2.5[1.0, 3.0, 0.0]

See also

abs, math.copysign, vec.abs, float

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