# coord_trans: Transformed cartesian coordinate system. In animint2: Animated Interactive Grammar of Graphics

## Description

`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.

## Usage

 ```1 2 3 4 5 6 7 8``` ```coord_trans( x = "identity", y = "identity", limx = NULL, limy = NULL, xtrans, ytrans ) ```

## Arguments

 `x, y` transformers for x and y axes `limx, limy` limits for x and y axes. (Named so for backward compatibility) `xtrans, ytrans` Deprecated; use `x` and `y` instead.

## Details

All current transformations only work with continuous values - see `trans_new` for list of transformations, and instructions on how to create your own.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59``` ```# 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)) # 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") ```

animint2 documentation built on Jan. 8, 2021, 5:39 p.m.