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ggplot2 (version 0.9.0)

coord_cartesian: Cartesian coordinates.

Description

The Cartesian coordinate system is the most familiar, and common, type of coordinate system. Setting limits on the coordinate system will zoom the plot (like you're looking at it with a magnifying glass), and will not change the underlying data like setting limits on a scale will.

Usage

coord_cartesian(xlim = NULL, ylim = NULL, wise = FALSE)

Arguments

xlim
limits for the x axis
ylim
limits for the y axis
wise
If TRUE will wisely expand the actual range of the plot a little, in the way that setting the limits on the scales does

Examples

Run this code
# There are two ways of zooming the plot display: with scales or
# with coordinate systems.  They work in two rather different ways.

(p <- qplot(disp, wt, data=mtcars) + geom_smooth())

# Setting the limits on a scale will throw away all data that's not
# inside these limits.  This is equivalent to plotting a subset of
# the original data
p + scale_x_continuous(limits = c(325, 500))

# Setting the limits on the coordinate system performs a visual zoom
# the data is unchanged, and we just view a small portion of the original
# plot.  See how the axis labels are the same as the original data, and
# the smooth continue past the points visible on this plot.
p + coord_cartesian(xlim = c(325, 500))

# You can see the same thing with this 2d histogram
(d <- ggplot(diamonds, aes(carat, price)) +
  stat_bin2d(bins = 25, colour="grey50"))

# When zooming the scale, the we get 25 new bins that are the same
# size on the plot, but represent smaller regions of the data space
d + scale_x_continuous(limits = c(0, 2))

# When zooming the coordinate system, we see a subset of original 50 bins,
# displayed bigger
d + coord_cartesian(xlim = c(0, 2))

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