qqnorm2t {Ecfun}  R Documentation 
Create a normal probability plot of y
with one line for each level of a
factor
or character
variable x
and (optionally) different
symbols for the different levels of a
variable z
.
To create a normal probability plot with
one line for each of multiple y
variables, see qqnorm2s
.
To create a normal probability plot with
one line and different symbols for each
level of a variable z
, see
qqnorm2
.
qqnorm2t(y, x, z=NULL, data., plot.it=TRUE,
datax=TRUE, outnames=NULL, pch=NULL,
col=c(1:4, 6), legend.=NULL, ...)
y 
a 
x 
a 
z 
A character vector giving the name of a
column of 
data. 
a 
plot.it 
logical: Should the result be plotted? 
datax 
The 
outnames 
Names for the components of the

pch 
a named vector of the plotting symbols to be
used with names corresponding to the levels
of By default, if If Otherwise, by default, If 
col 
A vector indicating the colors corresponding
to each element of 
legend. 
A list with components By default, Similarly, by default, 
... 
Optional arguments. For For 
data.
is split by x
and the
result is passed to qqnorm2s
Returns an object of class
qqnorm2s
.
Spencer Graves
##
## One data.frame
##
tstDF2 < data.frame(y=1:6, x=c('a','b'),
z2=c(TRUE, TRUE, FALSE),
z3=c('tell', 'me', 'why') )
# produce the object and plot it
Qnt < qqnorm2t('y', 'x', 'z2', tstDF2)
# plot the object previously created
plot(Qnt)
Qnt0 < qqnorm2t('y', 'x', data.=tstDF2)
# without z
qqnorm2t('y', 'x', data.=tstDF2)