coord_trans is different to scale transformations in that it occurs after statistical transformation and will affect the visual appearance of geoms - there is no guarantee that straight lines will continue to be straight.

coord_trans(x = "identity", y = "identity", limx = NULL,
limy = NULL, clip = "on", xtrans, ytrans)

## Arguments

x, y transformers for x and y axes limits for x and y axes. (Named so for backward compatibility) Should drawing be clipped to the extent of the plot panel? A setting of "on" (the default) means yes, and a setting of "off" means no. For details, please see coord_cartesian(). Deprecated; use x and y instead.

## Details

Transformations only work with continuous values: see scales::trans_new() for list of transformations, and instructions on how to create your own.

## Examples

# See ?geom_boxplot for other examples

# Three ways of doing transformation in ggplot:
#  * by transforming the data
ggplot(diamonds, aes(log10(carat), log10(price))) +
geom_point() #  * by transforming the scales
ggplot(diamonds, aes(carat, price)) +
geom_point() +
scale_x_log10() +
scale_y_log10() #  * by transforming the coordinate system:
ggplot(diamonds, aes(carat, price)) +
geom_point() +
coord_trans(x = "log10", y = "log10") # The difference between transforming the scales and
# transforming the coordinate system is that scale
# transformation occurs BEFORE statistics, and coordinate
# transformation afterwards.  Coordinate transformation also
# changes the shape of geoms:

d <- subset(diamonds, carat > 0.5)

ggplot(d, aes(carat, price)) +
geom_point() +
geom_smooth(method = "lm") +
scale_x_log10() +
scale_y_log10() ggplot(d, aes(carat, price)) +
geom_point() +
geom_smooth(method = "lm") +
coord_trans(x = "log10", y = "log10") # Here I used a subset of diamonds so that the smoothed line didn't
# drop below zero, which obviously causes problems on the log-transformed
# scale

# With a combination of scale and coordinate transformation, it's
# possible to do back-transformations:
ggplot(diamonds, aes(carat, price)) +
geom_point() +
geom_smooth(method = "lm") +
scale_x_log10() +
scale_y_log10() +
coord_trans(x = scales::exp_trans(10), y = scales::exp_trans(10))#> Warning: NaNs produced#> Warning: NaNs produced#> Warning: NaNs produced#> Warning: NaNs produced # cf.
ggplot(diamonds, aes(carat, price)) +
geom_point() +
geom_smooth(method = "lm") # Also works with discrete scales
df <- data.frame(a = abs(rnorm(26)),letters)
plot <- ggplot(df,aes(a,letters)) + geom_point()

plot + coord_trans(x = "log10") plot + coord_trans(x = "sqrt") 