dpois(x, lambda) ppois(q, lambda) qpois(p, lambda) rpois(n, lambda)
x
| vector of (positive) quantiles. |
p
| vector of probabilities. |
n
| number of random values to return. |
lambda
| vector of positive means. |
lambda. dpois gives the density,
ppois gives the distribution function qpois gives the
quantile function and rpois generates random deviates.
The Poisson distribution has density
p(x) = lambda^x exp(-lambda)/x!
for x = 0, 1, 2, ....dbinom for the binomial and dnbinom for
the negative binomial distribution.-log(dpois(0:7, lambda=1) * gamma(1+ 0:7)) Ni <- rpois(50, lam= 4); table(factor(Ni, 0:max(Ni)))