IdentifyA.Rd
Find all the points lying either in a rectangle area spanned by an upper left and a bottom-right point or by a polygon area consisting of any number of points defined by point and click.
IdentifyA(x, ...)
# S3 method for class 'formula'
IdentifyA (formula, data, subset, poly = FALSE, ...)
# Default S3 method
IdentifyA (x, y = NULL, poly = FALSE, ...)
x and y values of the points used to create the plot.
a formula
, such as y ~ x
specifying x and y values.
Here the formula must be entered that was used to create the scatterplot.
a data frame (or list) from which the variables in
formula
should be taken.
an optional vector specifying a subset of observations to be used.
logical. Defines if a polygon or a rectangle should be used to select the points. Default is rectangle.
If a polygon should be used, set this argument to TRUE
and select all desired points. The polygon will be closed
automatically when finished.
Other arguments to be passed to IdentifyA
.
Index vector with the points lying within the selected area.
The coordinates are returned as text in the attribute "cond"
.
if (FALSE) { # \dontrun{
# run the example via copy and paste
plot(temperature ~ delivery_min, data=d.pizza)
idx <- IdentifyA(temperature ~ delivery_min, data=d.pizza)
# you selected the following points
d.pizza[idx,]
points(temperature ~ delivery_min, data = d.pizza[idx,], col="green")
# use the attr("cond") for subsets in code
attr(idx, "cond")
# create a group variable for the found points
d.pizza$grp <- seq(nrow(d.pizza)) %in% idx
# try the polygon option
idx <- IdentifyA(temperature ~ delivery_min, data=d.pizza, poly=TRUE)
points(temperature ~ delivery_min, data = d.pizza[idx,], col="red")
} # }