7.5 Chi-Square Distribution

R script for chi-square distribution

Dchisq

## function (x2, nu) 
## {
##     if (nu <= 0) {
##         warning("bad nu for a Chi-square distribution")
##         return(NULL)
##     }
##     if (x2 <= 0) {
##         warning("bad x2 for a Chi-square distribution")
##         return(NULL)
##     }
##     return(exp(-0.5 * (x2 - (nu - 2) * log(x2)) - 0.693147180559945 * 
##         (0.5 * nu) - gammln(0.5 * nu)))
## }
## <bytecode: 0x000001e2a3fb9b40>
## <environment: namespace:math>

Pchisq

## function (x2, nu) 
## {
##     if (nu <= 0) {
##         warning("bad nu for a Chi-square distribution")
##         return(NULL)
##     }
##     if (x2 <= 0) {
##         warning("bad x2 for a Chi-square distribution")
##         return(NULL)
##     }
##     return(gammp(0.5 * nu, 0.5 * x2))
## }
## <bytecode: 0x000001e2a3f53ae0>
## <environment: namespace:math>

Qchisq

## function (p, nu) 
## {
##     if (nu <= 0) {
##         warning("bad nu for a Chi-square distribution")
##         return(NULL)
##     }
##     if (p < 0 | p >= 1) {
##         warning("bad p for a Chi-square distribution")
##         return(NULL)
##     }
##     return(2 * invgammp(p, 0.5 * nu))
## }
## <bytecode: 0x000001e2a3eee5d8>
## <environment: namespace:math>