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Math Common

scripts/vscripts/alyxlib/math/common.lua

Methods

sign

Get the sign of a number.

math:sign(x)

Parameters

  • x
    number
    The input number.

Returns - 1|0|-1 Returns 1 if the number is positive, -1 if the number is negative, or 0 if the number is zero.

trunc

Truncates a number to the specified number of decimal places.

math:trunc(number, places)

Parameters

  • number
    number
    The input number.The input number.
  • places (optional)
    integer
    The number of decimal places to keep.

Returns - number The input number truncated to the specified decimal places.

round

Rounds a number to the specified number of decimal places.

math:round(number, decimals)

Parameters

  • number
    number
    The input number to be rounded.
  • decimals (optional)
    integer
    The number of decimal places to round to. If not provided, the number will be rounded to the nearest whole number.

Returns - number The input number rounded to the specified decimal places or nearest whole number.

isclose

Checks if two numbers are close to each other within a specified tolerance.

Examples:

  1. Relative Tolerance (rel_tol): 

    local result1 = math.isclose(1000, 1020, 0.02)

    -- Expected Output: true

    -- Explanation: The difference (20) is within 2% of the larger number (1020), which allows a maximum difference of 20.4.

  2. Absolute Tolerance (abs_tol): 

    local result2 = math.isclose(1000, 1015, nil, 15)

    -- Expected Output: true

    -- Explanation: The difference (15) is within the fixed absolute tolerance of 15.


math:isclose(a, b, rel_tol, abs_tol)

Parameters

  • a
    number
    The first number to compare.
  • b
    number
    The second number to compare.
  • rel_tol (optional)
    number
    The relative tolerance (optional). Defines the maximum allowed relative difference between a and b as a percentage of the larger of the two values.
  • abs_tol (optional)
    number
    The absolute tolerance (optional). Defines the maximum allowed fixed difference between a and b, regardless of their magnitudes.

Returns - boolean Returns true if the numbers are considered close based on the specified tolerances; otherwise, returns false.

has_frac

Checks if a given number has a fractional part (decimal part).

math:has_frac(number)

Parameters

  • number
    number
    The number to check for fractional part.

Returns - boolean True if the number has a fractional part, false otherwise.

get_frac

Returns the fractional part of a number.

math:get_frac(number)

Parameters

  • number
    number
    The number to get the fractional part of.

Returns - number The fractional part of the number.