PHP 5.4.35 Released

stats_cdf_t

(PECL stats >= 1.0.0)

stats_cdf_tCalculates any one parameter of the T distribution given values for the others.

Description

float stats_cdf_t ( float $par1 , float $par2 , int $which )
Warning

This function is currently not documented; only its argument list is available.

Parameters

par1

par2

which

Return Values

add a note add a note

User Contributed Notes 2 notes

up
3
Brian
4 years ago
In order to match the output of this function with Excel's TDIST function, you must take 1 - the value.  For example, for a two-tailed T-distribution for x=4 and degrees of freedom=2, the formula would be:

(1 - stats_cdf_t(4, 2, 1)) * 2

For a single tail, do not include the multiply by 2 portion.
up
1
Anonymous
2 years ago
Input  and return values of stats_cdf_t depends on the $which-parameter:
<?php
function get_t_p($t, $df){
  return
stats_cdf_t($t, $df, 1);
}
function
get_t_t($p, $df){
  return
stats_cdf_t($p, $df, 2);
}
function
get_t_df($p, $t){
  return
stats_cdf_t($p, $t, 3);
}
?>
To Top