Difference between revisions of "Math.frexp"

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m (Text replacement - "</source>" to "</syntaxhighlight>")
 
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__NOTOC__
 
__NOTOC__
 
'''Available since:''' Gideros 2011.6<br/>
 
'''Available since:''' Gideros 2011.6<br/>
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'''Class:''' [[math]]<br/>
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=== Description ===
 
=== Description ===
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Returns m and e such that v = m2^e, e is an integer and the absolute value of m is in the range [0.5, 1) (or zero when v is zero).
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Used to split a floating-point number (v) into a normalized fraction (a mantissa) and an integer exponent.
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<source lang="lua">
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<syntaxhighlight lang="lua">
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(number) = math.frexp(v)
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(number) (number) = math.frexp(v)
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</source>
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</syntaxhighlight>
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'''v''': (number) value ''''''<br/>
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'''Returns''' (number) result<br/>
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Returns m and e such that v = m*2^e, e is an integer and the absolute value of m is in the range [0.5, 1) (or zero when v is zero). The mantissa has the same sign as the argument v.
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=== Parameters ===
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'''v''': (number) value<br/>
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=== Return values ===
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'''Returns''' (number) the mantissa, a multiplier in the range [0.5, 1) (normalized fraction)<br/>
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'''Returns''' (number) the exponent as an integer<br/>
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=== Example ===
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<syntaxhighlight lang="lua">
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local m, n = math.frexp(16.4)
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print("mantissa", m, "exponent", n) -- mantissa 0.5125 exponent 5
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print(m*2^n) -- 16.4
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</syntaxhighlight>
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=== Note ===
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[[math.ldexp]] is the inverse operation.
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{{Math}}

Latest revision as of 15:30, 13 July 2023

Available since: Gideros 2011.6
Class: math

Description

Used to split a floating-point number (v) into a normalized fraction (a mantissa) and an integer exponent. 

(number) (number) = math.frexp(v)

Returns m and e such that v = m*2^e, e is an integer and the absolute value of m is in the range [0.5, 1) (or zero when v is zero). The mantissa has the same sign as the argument v.

Parameters

v: (number) value

Return values

Returns (number) the mantissa, a multiplier in the range [0.5, 1) (normalized fraction)
Returns (number) the exponent as an integer

Example

local m, n = math.frexp(16.4)
print("mantissa", m, "exponent", n) -- mantissa 0.5125 exponent 5
print(m*2^n) -- 16.4

Note

math.ldexp is the inverse operation.




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