addnorm {MQMF}

addnorm adds a normal distribution to a histogram of a data set.

Description

addnorm adds a normal distribution to a histogram of a data set. This is generally to be used to illustrate whether log-transformation normalizes a set of catch or cpue data.

Usage

addnorm(inhist, xdata, inc = 0.01)

Arguments

inhist

is the output from a call to 'hist' (see examples)

xdata

is the data that is being plotted in the histogram.

inc

defaults to a value of 0.01; is the fine grain increment used to define the normal curve. The histogram breaks should be coarse grained relative to inc.

Value

a list with a vector of 'x' values and a vector of 'y' values (to be used to plot the fitted normal probability density function), and a vector called 'stats' containing the mean and standard deviation of the input data

Examples

 oldpar <- par(no.readonly=TRUE)
 x <- rnorm(1000,mean=5,sd=1)
 #plotprep(height=6,width=4,newdev=FALSE)
 par(mfrow= c(1,1),mai=c(0.5,0.5,0.3,0.05))
 par(cex=0.75, mgp=c(1.5,0.35,0), font.axis=7)
 outH <- hist(x,breaks=25,col=3,main="")
 nline <- addnorm(outH,x)
 lines(nline$x,nline$y,lwd=3,col=2)
 print(nline$stats)
 par(oldpar)