PHPOffice /
PhpSpreadsheet
| @@ 1062-1106 (lines=45) @@ | ||
| 1059 | * @param float $degrees degrees of freedom |
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| 1060 | * @return float |
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| 1061 | */ |
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| 1062 | public static function CHIINV($probability, $degrees) |
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| 1063 | { |
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| 1064 | $probability = Functions::flattenSingleValue($probability); |
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| 1065 | $degrees = floor(Functions::flattenSingleValue($degrees)); |
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| 1066 | ||
| 1067 | if ((is_numeric($probability)) && (is_numeric($degrees))) { |
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| 1068 | $xLo = 100; |
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| 1069 | $xHi = 0; |
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| 1070 | ||
| 1071 | $x = $xNew = 1; |
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| 1072 | $dx = 1; |
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| 1073 | $i = 0; |
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| 1074 | ||
| 1075 | while ((abs($dx) > PRECISION) && ($i++ < MAX_ITERATIONS)) { |
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| 1076 | // Apply Newton-Raphson step |
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| 1077 | $result = self::CHIDIST($x, $degrees); |
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| 1078 | $error = $result - $probability; |
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| 1079 | if ($error == 0.0) { |
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| 1080 | $dx = 0; |
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| 1081 | } elseif ($error < 0.0) { |
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| 1082 | $xLo = $x; |
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| 1083 | } else { |
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| 1084 | $xHi = $x; |
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| 1085 | } |
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| 1086 | // Avoid division by zero |
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| 1087 | if ($result != 0.0) { |
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| 1088 | $dx = $error / $result; |
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| 1089 | $xNew = $x - $dx; |
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| 1090 | } |
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| 1091 | // If the NR fails to converge (which for example may be the |
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| 1092 | // case if the initial guess is too rough) we apply a bisection |
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| 1093 | // step to determine a more narrow interval around the root. |
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| 1094 | if (($xNew < $xLo) || ($xNew > $xHi) || ($result == 0.0)) { |
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| 1095 | $xNew = ($xLo + $xHi) / 2; |
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| 1096 | $dx = $xNew - $x; |
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| 1097 | } |
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| 1098 | $x = $xNew; |
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| 1099 | } |
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| 1100 | if ($i == MAX_ITERATIONS) { |
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| 1101 | return Functions::NA(); |
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| 1102 | } |
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| 1103 | return round($x, 12); |
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| 1104 | } |
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| 1105 | return Functions::VALUE(); |
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| 1106 | } |
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| 1107 | ||
| 1108 | ||
| 1109 | /** |
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| @@ 3354-3398 (lines=45) @@ | ||
| 3351 | * @param float $degrees degrees of freedom |
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| 3352 | * @return float |
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| 3353 | */ |
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| 3354 | public static function TINV($probability, $degrees) |
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| 3355 | { |
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| 3356 | $probability = Functions::flattenSingleValue($probability); |
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| 3357 | $degrees = floor(Functions::flattenSingleValue($degrees)); |
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| 3358 | ||
| 3359 | if ((is_numeric($probability)) && (is_numeric($degrees))) { |
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| 3360 | $xLo = 100; |
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| 3361 | $xHi = 0; |
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| 3362 | ||
| 3363 | $x = $xNew = 1; |
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| 3364 | $dx = 1; |
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| 3365 | $i = 0; |
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| 3366 | ||
| 3367 | while ((abs($dx) > PRECISION) && ($i++ < MAX_ITERATIONS)) { |
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| 3368 | // Apply Newton-Raphson step |
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| 3369 | $result = self::TDIST($x, $degrees, 2); |
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| 3370 | $error = $result - $probability; |
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| 3371 | if ($error == 0.0) { |
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| 3372 | $dx = 0; |
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| 3373 | } elseif ($error < 0.0) { |
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| 3374 | $xLo = $x; |
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| 3375 | } else { |
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| 3376 | $xHi = $x; |
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| 3377 | } |
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| 3378 | // Avoid division by zero |
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| 3379 | if ($result != 0.0) { |
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| 3380 | $dx = $error / $result; |
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| 3381 | $xNew = $x - $dx; |
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| 3382 | } |
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| 3383 | // If the NR fails to converge (which for example may be the |
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| 3384 | // case if the initial guess is too rough) we apply a bisection |
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| 3385 | // step to determine a more narrow interval around the root. |
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| 3386 | if (($xNew < $xLo) || ($xNew > $xHi) || ($result == 0.0)) { |
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| 3387 | $xNew = ($xLo + $xHi) / 2; |
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| 3388 | $dx = $xNew - $x; |
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| 3389 | } |
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| 3390 | $x = $xNew; |
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| 3391 | } |
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| 3392 | if ($i == MAX_ITERATIONS) { |
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| 3393 | return Functions::NA(); |
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| 3394 | } |
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| 3395 | return round($x, 12); |
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| 3396 | } |
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| 3397 | return Functions::VALUE(); |
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| 3398 | } |
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| 3399 | ||
| 3400 | ||
| 3401 | /** |
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