JordanRL /
Fermat
| @@ 33-45 (lines=13) @@ | ||
| 30 | $this->sd = $sd; |
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| 31 | } |
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| 32 | ||
| 33 | public static function makeFromMean($p, $x, $mean) |
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| 34 | {
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| 35 | $one = Numbers::makeOne(); |
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| 36 | $p = Numbers::makeOrDont(Numbers::IMMUTABLE, $p); |
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| 37 | $x = Numbers::makeOrDont(Numbers::IMMUTABLE, $x); |
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| 38 | $mean = Numbers::makeOrDont(Numbers::IMMUTABLE, $mean); |
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| 39 | ||
| 40 | $z = Stats::inverseNormalCDF($one->subtract($p)); |
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| 41 | ||
| 42 | $sd = $x->subtract($mean)->divide($z); |
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| 43 | ||
| 44 | return new Normal($mean, $sd); |
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| 45 | } |
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| 46 | ||
| 47 | public static function makeFromSd($p, $x, $sd) |
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| 48 | {
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| @@ 47-59 (lines=13) @@ | ||
| 44 | return new Normal($mean, $sd); |
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| 45 | } |
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| 46 | ||
| 47 | public static function makeFromSd($p, $x, $sd) |
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| 48 | {
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| 49 | $one = Numbers::makeOne(); |
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| 50 | $p = Numbers::makeOrDont(Numbers::IMMUTABLE, $p); |
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| 51 | $x = Numbers::makeOrDont(Numbers::IMMUTABLE, $x); |
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| 52 | $sd = Numbers::makeOrDont(Numbers::IMMUTABLE, $sd); |
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| 53 | ||
| 54 | $z = Stats::inverseNormalCDF($one->subtract($p)); |
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| 55 | ||
| 56 | $mean = $x->subtract($z->multiply($sd)); |
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| 57 | ||
| 58 | return new Normal($mean, $sd); |
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| 59 | } |
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| 60 | ||
| 61 | public function cdf($x) |
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| 62 | {
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