LOLWOZ (via thedailywhat)
TI-84 statistics functions (nCr, binomcdf, binompdf, factorials) implemented in PHP
<?php
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function nCr($n, $k) {
//Valid for 0 <= k <= n
return factorial($n)/(factorial($k)*factorial($n - $k));
}
function factorial($n) {
$f = 1;
for($i = 1; $i <= $n; $i++) {
$f = $f*$i;
}
return $f;
}
function binompdf($n, $p, $k) {
return nCr($n, $k)*pow($p, $k)*pow(1-$p, $n-$k);
}
function binomcdf($n, $p, $k) {
$b = 0;
for($i = 0; $i <= $k; $i++) {
$b = $b+binompdf($n, $p, $i);
}
return $b;
}
?>
