nos.qqnorm {NostalgiR}

nos.qqnorm text-based normal quantile-quantile plots

Description

Produces a text-based normal quantile-quantile plot where the theoretical quantiles are plotted along the x-axis and the sample quantiles are plotted along the y-axis.

Usage

nos.qqnorm(data, line = T, ratio = 0.25, width = round(options()$width *
  0.8), height = round(ratio * width), pch = c("o", "~"))

Arguments

data

A numeric vector containing the values to be plotted. NA and NaN are allowed, but are removed for the plot. Infinities will cause an error.

line

If TRUE, the line of theoretical quantile equality is plotted. If FALSE, then the line of theoretical quantile equality is not plotted.

ratio

Coefficient that controls the aspect ratio of the plot.

width

Width of the plot in points.

height

Height of the plot in points.

pch

A two dimensional vector of single-character symbols. The first symbol is for data point, and the second symbol is for the line of theoretical quantile equality.

Note

Due to rounding to a relatively crude grid results can only be approximate. The equally spaced axis ticks, for example, may be non-equally spaced in the plot. Further, due to the crude grid also there might be several points per character. The function uses the same plotting symbol no matter how many points coincide on one character position.

Author(s)

Hien D. Nguyen

See Also

qqnorm, qqline and txtplot.

Examples

## Produce a normal quantile-quantile plot of 10 random standard normal points,
## without the line of theoretical quantile equality.
data <- rnorm(10)
nos.qqnorm(data,line=FALSE)

## Produce a normal quantile-quantile plot of 100 random chi-squared(3) points,
## with the line of theoretical quantile equality.
data <- rchisq(100,3)
nos.qqnorm(data)