Welch's t-test: Difference between revisions

Content added Content deleted
m (contradiction with the following sentence (it's a translation of a specific R command))
m (→‎{{header|C}}: removed redundant variable 'x', should save RAM and make easier to read)
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);
);
// printf("Welch = %lf DOF = %lf\n", WELCH_T_STATISTIC, DEGREES_OF_FREEDOM);
// printf("Welch = %lf DOF = %lf\n", WELCH_T_STATISTIC, DEGREES_OF_FREEDOM);
const double a = DEGREES_OF_FREEDOM/2, x = DEGREES_OF_FREEDOM/(WELCH_T_STATISTIC*WELCH_T_STATISTIC+DEGREES_OF_FREEDOM);
const double a = DEGREES_OF_FREEDOM/2;
double value = DEGREES_OF_FREEDOM/(WELCH_T_STATISTIC*WELCH_T_STATISTIC+DEGREES_OF_FREEDOM);
if ((isinf(x) != 0) || (isnan(x) != 0)) {
if ((isinf(value) != 0) || (isnan(value) != 0)) {
return 1.0;
return 1.0;
}
}
if ((isinf(a) != 0) || (isnan(a) != 0)) {
if ((isinf(value) != 0) || (isnan(value) != 0)) {
return 1.0;
return 1.0;
}
}


/* Purpose:
/* Purpose:


BETAIN computes the incomplete Beta function ratio.
BETAIN computes the incomplete Beta function ratio.
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double temp;
double temp;
double term;
double term;
double value;
double xx;
double xx;


value = x;
// ifault = 0;
// ifault = 0;
//Check the input arguments.
//Check the input arguments.
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// return value;
// return value;
}
}
if ( x < 0.0 || 1.0 < x )
if ( value < 0.0 || 1.0 < value )
{
{
// *ifault = 2;
// *ifault = 2;
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Special cases.
Special cases.
*/
*/
if ( x == 0.0 || x == 1.0 ) {
if ( value == 0.0 || value == 1.0 ) {
return value;
return value;
}
}
psq = a + 0.5;
psq = a + 0.5;
cx = 1.0 - x;
cx = 1.0 - value;


if ( a < psq * x )
if ( a < psq * value )
{
{
xx = cx;
xx = cx;
cx = x;
cx = value;
pp = 0.5;
pp = 0.5;
qq = a;
qq = a;
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else
else
{
{
xx = x;
xx = value;
pp = a;
pp = a;
qq = 0.5;
qq = 0.5;
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}
}
}
}

return value;
return value;
}
}
Retrieved from "https://rosettacode.org/wiki/Welch%27s_t-test"