ran.unif.exp.norm: Custom random number generators for didactic purposes
In seem: Simulation of Ecological and Environmental Models

Description Usage Arguments Details Value Note Author(s) References See Also Examples

Random generator of uniform RV between a and b, exponential, and standard normal RV

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ran.unif(a,b)
ran.exp(rate)
ran.norm()

`a`	lower value
`b`	upper value
`rate`	rate parameter of exponential RV

For didactic purposes, we show how to build custom random number generators from the basic uniform distribution between 0 and 1. The following function defines a uniform generator between a and b using the scaling and shifting of U(0,1).

One value of a RV according to distribution selected

Didactic purposes. Use runif,rexp, rnorm for your real work.

Miguel F. Acevedo Acevedo@unt.edu

Acevedo M.F. 2012. Simulation of Ecological and Environmental Models. CRC Press.

Random number generators runif, rexp, rnorm

yunif <- array(); a <- 5;b <- 15
for(i in 1:10) yunif[i] <- ran.unif(a,b)
hist(yunif,prob=TRUE); title(sub="Uniform in 5,15") 

yexp <- array(); rate <- 1/10
for(i in 1:10) yexp[i] <- ran.exp(rate)
hist(yexp,prob=TRUE); title(sub="Exponential of rate 0.1") 

ynorm <- array(); 
for(i in 1:10) ynorm[i] <- ran.norm()
hist(ynorm,prob=TRUE); title(sub="Std Normal")