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Math Common

scripts/vscripts/alyxlib/math/common.lua

Methods

sign

Gets the sign of a number.

math:sign(x)

Parameters

  • x
    number
    The input number

Returns - -1|0|1 Sign of the number: -1 for negative, 1 for positive, 0 if zero

trunc

Truncates a number to a given number of decimal places.

math:trunc(number, places)

Parameters

  • number
    number
    The number to truncate
  • places (optional)
    integer
    Decimal places to truncate to (default: 0)

Returns - number The truncated number

round

Rounds a number to a given number of decimal places.

math:round(number, decimals)

Parameters

  • number
    number
    The number to be rounded
  • decimals (optional)
    integer
    Decimal places to round to (default: 0)

Returns - number The rounded 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
    Defines the maximum allowed relative difference between a and b as a percentage of the larger of the two values
  • abs_tol (optional)
    number
    Defines the maximum allowed fixed difference between a and b, regardless of their magnitudes

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

has_frac

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

math:has_frac(number)

Parameters

  • number
    number
    The number to check

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