dchisq(x, df) pchisq(q, df) qchisq(p, df) rchisq(n, df)
df
degrees of freedom. dchisq
gives the density,
pchisq
gives the distribution function qchisq
gives
the quantile function and rchisq
generates random deviates.
The chi-square distribution with df
= n degrees of freedom has density
f(x) = 1 / (2^(n/2) Gamma(n/2)) x^(n/2-1) e^(-x/2)
for x > 0.dnchisq
, dgamma
, dexp
.
dchisq(1, df=1:3) x <- 1:10 ## Chisquare( df = 2) is a special exponential distribution dchisq(x, df=2) == dexp(x, 1/2) pchisq(x, df=2) == pexp(x, 1/2)#- only approximately