Exporting a graph is often a chore, especially if you want to have the best looking graphs in your publications. One common problem is that it is usually difficult to predict how the text contained in the graph will look once in its final location (i.e. in your document). You may end up with text looking either too big or too small.
fplot provides a set of tools to simplify graph
exportation. This is achieved thanks to a different philosophy from
existing export functions: instead of giving the target size of the
figure (width/height), just give the desired point size of the text. The
graph will be created such that once it’s in your final document, the
size of the text in the graph will be equal to the desired point
In essence, it’s a reparametrization of existing export functions. Below a simple example is detailed.
You can export any kind of graph with the functions
But first things first, you need to provide the size the image will take in your final document.
By default, the target location of the graph is a US letter
page with “normal” margins (i.e. 2.5cm left and right, 2cm top and
bottom). You can change it globally with the function
setFplot_page. Let’s change it to A4 and one inch margins
on all sides:
library(fplot) setFplot_page(page = "a4", margins = 1)
Now let’s go for the first export:
export_graph_start("first_export.pdf") plot(1, 1, type = "n", ann = FALSE) text(1, 1, "This text will be displayed in 10pt.") export_graph_end()
You can notice that in the end of the export,
export_graph_end is used in lieu of
(which must be familier to the ones used to export with base R tools).
This function does the same thing as
dev.off but also
displays the exported graph in the Viewer pane of RStudio or VSCode
(provided you use it). This way you can directly see how the exported
What about the geometry of the graph? By default the width of the
plot is 100% of the text width. You can change it with the
width argument: e.g. using relative widths
width = 0.5 (50% of the text width),
width = "50%" (idem), or absolute widths
width = "10cm",
width = "5in", etc.
The width to height ratio can be modified with the
argument (or you can use
h2w for the inverse ratio). The
w2h = 1.75 (close to the Golden ratio).
Finally the default point size is
pt = 10. If embedded
in an A4 page with 1 inch margins on both sides, the text of the
previously exported graph would be in 10pt:
If you increase the pt size that’s what you would get:
export_graph_start("second_export.pdf", pt = 12) plot(1, 1, type = "n", ann = FALSE) text(1, 1, "This text will be displayed in 12pt.") export_graph_end()
As we can see, with a larger font any text is larger, and since there is text in the margins, the plotting region becomes smaller.
With this way of exporting, you need to worry only on two things:
To create the same graph as before but which would take the total
height of the page, just use the argument
height = 1
height = 100% or
height = 1th, th
meaning text height would also
export_graph_start("third_export.pdf", pt = 12, height = 1) plot(1, 1, type = "n", ann = FALSE) text(1, 1, "This text will be displayed in 12pt.") export_graph_end()
Finally if you use
sideways = TRUE, the settings become
width = 1th (100% text height) and
height = 0.9tw (90% text width), i.e. the graph would take
the full page except a 10% space left for the graph legend.
# You can also set the point size globally setFplot_page(pt = 12) export_graph_start("fourth_export.pdf", sideways = TRUE) plot(1, 1, type = "n", ann = FALSE) text(1, 1, "This text will be displayed in 12pt.") export_graph_end()
export_graph_endreplace the family of functions