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39 lines
2.0 KiB
ReStructuredText
39 lines
2.0 KiB
ReStructuredText
Rounding functions
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----------------
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floor(x[, N])
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~~~~~~~
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Returns a rounder number that is less than or equal to 'x'.
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A round number is a multiple of 1 / 10N, or the nearest number of the appropriate data type ``if 1 / 10N`` isn't exact.
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'N' is an integer constant, optional parameter. By default it is zero, which means to round to an integer.
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'N' may be negative.
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Examples: ``floor(123.45, 1) = 123.4, floor(123.45, -1) = 120``.
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'x' is any numeric type. The result is a number of the same type.
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For integer arguments, it makes sense to round with a negative 'N' value (for non-negative 'N', the function doesn't do anything).
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If rounding causes overflow (for example, ``floor(-128, -1))``, an implementation-specific result is returned.
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ceil(x[, N])
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~~~~~~
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Returns the smallest round number that is greater than or equal to 'x'. In every other way, it is the same as the 'floor' function (see above)..
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round(x[, N])
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~~~~~~~
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Returns the round number nearest to 'num', which may be less than, greater than, or equal to 'x'.
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If 'x' is exactly in the middle between the nearest round numbers, one of them is returned (implementation-specific).
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The number '-0.' may or may not be considered round (implementation-specific).
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In every other way, this function is the same as 'floor' and 'ceil' described above.
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roundToExp2(num)
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~~~~~~~~
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Accepts a number. If the number is less than one, it returns 0. Otherwise, it rounds the number down to the nearest (whole non-negative) degree of two.
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roundDuration(num)
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~~~~~~~~
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Accepts a number. If the number is less than one, it returns 0. Otherwise, it rounds the number down to numbers from the set: 1, 10, 30, 60, 120, 180, 240, 300, 600, 1200, 1800, 3600, 7200, 18000, 36000. This function is specific to Yandex.Metrica and used for implementing the report on session length.
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roundAge(num)
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~~~~~~~
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Accepts a number. If the number is less than 18, it returns 0. Otherwise, it rounds the number down to numbers from the set: 18, 25, 35, 45, 55. This function is specific to Yandex.Metrica and used for implementing the report on user age.
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