﻿ How to Specify the Size of a Graph in Ggplot2 Independent of Axis Labels - ITCodar

# How to Specify the Size of a Graph in Ggplot2 Independent of Axis Labels

## How to specify the size of a graph in ggplot2 independent of axis labels

Use `ggplotGrob`. Something like this:

``g1 <- ggplot(...)g2 <- ggplot(...)g1grob <- ggplotGrob(g1)g2grob <- ggplotGrob(g2)grid.arrange(g1grob, g2grob)``

## How to maintain size of ggplot with long labels

There a several ways to avoid overplotting of labels or squeezing the plot area or to improve readability in general. Which of the proposed solutions is most suitable will depend on the lengths of the labels and the number of bars, and a number of other factors. So, you will probably have to play around.

#### Dummy data

Unfortunately, the OP hasn't included a reproducible example, so we we have to make up our own data:

``V1 <- c("Long label", "Longer label", "An even longer label",        "A very, very long label", "An extremely long label",        "Long, longer, longest label of all possible labels",         "Another label", "Short", "Not so short label")df <- data.frame(V1, V2 = nchar(V1))yaxis_label <- "A rather long axis label of character counts"``

#### "Standard" bar chart

Labels on the x-axis are printed upright, overplotting each other:

``library(ggplot2)  # version 2.2.0+p <- ggplot(df, aes(V1, V2)) + geom_col() + xlab(NULL) +  ylab(yaxis_label) p``

Note that the recently added `geom_col()` instead of `geom_bar(stat="identity")` is being used. #### OP's approach: rotate labels

Labels on x-axis are rotated by 90° degrees, squeezing the plot area:

``p + theme(axis.text.x = element_text(angle = 90))`` #### Horizontal bar chart

All labels (including the y-axis label) are printed upright, improving readability but still squeezing the plot area (but to a lesser extent as the chart is in landscape format):

``p + coord_flip()`` #### Vertical bar chart with labels wrapped

Labels are printed upright, avoiding overplotting, squeezing of plot area is reduced. You may have to play around with the `width` parameter to `stringr::str_wrap`.

``q <- p + aes(stringr::str_wrap(V1, 15), V2) + xlab(NULL) +  ylab(yaxis_label)q`` #### Horizontal bar chart with labels wrapped

My favorite approach: All labels are printed upright, improving readability,
squeezing of plot area are is reduced. Again, you may have to play around with the `width` parameter to `stringr::str_wrap` to control the number of lines the labels are split into.

``q + coord_flip()`` #### Addendum: Abbreviate labels using `scale_x_discrete()`

For the sake of completeness, it should be mentioned that `ggplot2` is able to abbreviate labels. In this case, I find the result disappointing.

``p + scale_x_discrete(labels = abbreviate)`` ## How to arrange `ggplot2` objects side-by-side and ensure equal plotting areas?

One suggestion: the `patchwork` package.

``library(patchwork)plot_a + plot_b`` It also works for more complex layouts, e.g.:

``(plot_a | plot_b) / plot_a`` ## How can I make consistent-width plots in ggplot (with legends)?

Edit: Very easy with `egg` package

``# install.packages("egg")library(egg)p1 <- ggplot(data.frame(x=c("a","b","c"),                        y=c("happy","sad","ambivalent about life")),             aes(x=factor(0),fill=x)) +       geom_bar()p2 <- ggplot(data.frame(x=c("a","b","c"),                        y=c("happy","sad","ambivalent about life")),             aes(x=factor(0),fill=y)) +       geom_bar()ggarrange(p1,p2, ncol = 1)``

Original Udated to ggplot2 2.2.1

Here's a solution that uses functions from the `gtable` package, and focuses on the widths of the legend boxes. (A more general solution can be found here.)

``library(ggplot2)   library(gtable)    library(grid)library(gridExtra) # Your plotsp1 <- ggplot(data.frame(x=c("a","b","c"),y=c("happy","sad","ambivalent about life")),aes(x=factor(0),fill=x)) + geom_bar()p2 <- ggplot(data.frame(x=c("a","b","c"),y=c("happy","sad","ambivalent about life")),aes(x=factor(0),fill=y)) + geom_bar()# Get the gtablesgA <- ggplotGrob(p1)gB <- ggplotGrob(p2)# Set the widthsgA\$widths <- gB\$widths# Arrange the two charts.# The legend boxes are centeredgrid.newpage()grid.arrange(gA, gB, nrow = 2)``

If in addition, the legend boxes need to be left justified, and borrowing some code from here written by @Julius

``p1 <- ggplot(data.frame(x=c("a","b","c"),y=c("happy","sad","ambivalent about life")),aes(x=factor(0),fill=x)) + geom_bar()p2 <- ggplot(data.frame(x=c("a","b","c"),y=c("happy","sad","ambivalent about life")),aes(x=factor(0),fill=y)) + geom_bar()# Get the widthsgA <- ggplotGrob(p1)gB <- ggplotGrob(p2)# The parts that differs in widthleg1 <- convertX(sum(with(gA\$grobs[], grobs[]\$widths)), "mm")leg2 <- convertX(sum(with(gB\$grobs[], grobs[]\$widths)), "mm")# Set the widthsgA\$widths <- gB\$widths# Add an empty column of "abs(diff(widths)) mm" width on the right of # legend box for gA (the smaller legend box)gA\$grobs[] <- gtable_add_cols(gA\$grobs[], unit(abs(diff(c(leg1, leg2))), "mm"))# Arrange the two chartsgrid.newpage()grid.arrange(gA, gB, nrow = 2)`` Alternative solutions There are `rbind` and `cbind` functions in the `gtable` package for combining grobs into one grob. For the charts here, the widths should be set using `size = "max"`, but the CRAN version of `gtable` throws an error.

One option: It should be obvious that the legend in the second plot is wider. Therefore, use the `size = "last"` option.

``# Get the grobsgA <- ggplotGrob(p1)gB <- ggplotGrob(p2)# Combine the plotsg = rbind(gA, gB, size = "last")# Draw itgrid.newpage()grid.draw(g)``

Left-aligned legends:

``# Get the grobsgA <- ggplotGrob(p1)gB <- ggplotGrob(p2)# The parts that differs in widthleg1 <- convertX(sum(with(gA\$grobs[], grobs[]\$widths)), "mm")leg2 <- convertX(sum(with(gB\$grobs[], grobs[]\$widths)), "mm")# Add an empty column of "abs(diff(widths)) mm" width on the right of # legend box for gA (the smaller legend box)gA\$grobs[] <- gtable_add_cols(gA\$grobs[], unit(abs(diff(c(leg1, leg2))), "mm"))# Combine the plotsg = rbind(gA, gB, size = "last")# Draw itgrid.newpage()grid.draw(g)``

A second option is to use `rbind` from Baptiste's `gridExtra` package

``# Get the grobsgA <- ggplotGrob(p1)gB <- ggplotGrob(p2)# Combine the plotsg = gridExtra::rbind.gtable(gA, gB, size = "max")# Draw itgrid.newpage()grid.draw(g)``

Left-aligned legends:

``# Get the grobsgA <- ggplotGrob(p1)gB <- ggplotGrob(p2)# The parts that differs in widthleg1 <- convertX(sum(with(gA\$grobs[], grobs[]\$widths)), "mm")leg2 <- convertX(sum(with(gB\$grobs[], grobs[]\$widths)), "mm")# Add an empty column of "abs(diff(widths)) mm" width on the right of # legend box for gA (the smaller legend box)gA\$grobs[] <- gtable_add_cols(gA\$grobs[], unit(abs(diff(c(leg1, leg2))), "mm"))# Combine the plotsg = gridExtra::rbind.gtable(gA, gB, size = "max")# Draw itgrid.newpage()grid.draw(g)``

## Change axes label and scale using ggplot and patchwork in R

``library(ggplot2)library(patchwork)d <- carsd\$Obs <- c(1:50)f1 <- function(a, y_lab) {  ggplot(data = d, aes_string(x = "Obs", y = a)) +    geom_line() +    scale_y_continuous(limits = range(c(d\$speed, d\$dist))) +    labs(x = "Observation", y = y_lab)}f1("speed", "Speed") + f1("dist", "Distance")`` ## ggplot with 2 y axes on each side and different scales

Sometimes a client wants two y scales. Giving them the "flawed" speech is often pointless. But I do like the ggplot2 insistence on doing things the right way. I am sure that ggplot is in fact educating the average user about proper visualization techniques.

Maybe you can use faceting and scale free to compare the two data series? - e.g. look here: https://github.com/hadley/ggplot2/wiki/Align-two-plots-on-a-page

## allign dimensions of separat plots

Inside cowplot, there is a function `align_margin` that aligns your left and right margins in a list of ggplot grobs.

We include a few more plots:

``p1 <- ggplot(iris, aes(Sepal.Length, Species)) +     geom_density_ridges() p2 <- ggplot(mtcars) +     geom_point(aes(mpg, disp))p3 <- ggplot(PlantGrowth) +     geom_boxplot(aes(group, weight))p4 <- ggplot(USArrests) +     geom_point(aes(Assault, UrbanPop))``

With some slight modification from the vignette:

``grobs <- lapply(list(p1, p2, p3,p4), as_grob)plot_widths <- lapply(grobs, function(x) {x\$widths})aligned_widths <- align_margin(align_margin(plot_widths, "first"),"last")# reset widthsfor (i in seq_along(plots)) {       grobs[[i]]\$widths <- aligned_widths[[i]]     }``

To get all in a page:

``plot_grid(plotlist = grobs, ncol = 1)``

To get individual:

``grid.draw(grobs[])``