Diagrams

Of the kind I need, a practical guide to the creation thereof


Amie Wilkinson’s blackboard

Amie Wilkinson’s blackboard

On the art and science of scientific line drawings. I am especially interested in scientific diagrams; drafting/CAD/engineering stuff is different field again.

I am also interested in diagrams that are some mix of freehand and procedural; maybe partly generated algorithmically and partly through a GUI. This is obviously one of those combinations that you imagine would be wonderful but do not find often, like a billionaire media mogul who also believes in climate action.

Generally I would like these to export to a modern compatible vector format which means SVG, PDF or, as a fallback, one of these other formats that can be converted to the above to, such as Adobe Illustrator, EPS or xfig.

Awesome examples of diagrams

Gallery of concept visualisation: gallery of methods for explaining complex ideas; everything from exotic 3d stuff to crayon drawing and sticks.

See also interactive visualisations.

The tedious mechanics of manufacturing those awesome examples

Sketching vector diagrams for your reports: More painful than it should be.

Here’s the stack exchange list.

What follows is my list, in descending order of (fluctuating) frequency of use.

Notice there are no commercial entrants in this race? I’m too poor for any Autodesk product, and unconvinced of their utility unless I wish to build some kind of major concrete structure. I did buy Omnigraffle, the much-touted diagram editor for macOS. What a disaster; expensive, unintuitive, over-engineered. Like they ripped off xfig, took out the API and compensated for it by putting bezels on the icons. If you want to waste hours with horribly inscrutable drafting products, there are many open-source options available that can give you that experience for free.

ipe

ipe has, if not a actually intuitive interface, the closest I have seen to an intuitive interface in a scientific sketch program. It’s simple to learn, although has oddities - e.g. you change the page size by creating and importing an XML stylesheet. Riiiight.

Also, it can’t export SVG, merely PDF and EPS, each of which are not so much vector graphics standards, as the battleground beneath the standards behind which the corporate armies clash.

Anyway, it repays persistence.

Ipe’s main features are:

  • Entry of text as LaTeX source code. This makes it easy to enter mathematical expressions, and to reuse the LaTeX-macros of the main document. …
  • Produces pure Postscript/PDF, including the text…
  • It is easy to align objects with respect to each other (for instance, to place a point on the intersection of two lines, or to draw a circle through three given points) using various snapping modes…

That last point sounds minor, but it is an ingenious move that makes all the other terrible design choices worthwhile. Anyone who has every spent 90 minutes on doing trigonometry to get a pstricks diagram right, and wondered what happened to the thing where computers eliminated drudge work, you will weep upon the sight of it.

Has built-in Lua scripting, like everything on the planet. Integrates with matplotlib.

Recommended: handy user contributions by Stefan Huber.

See pdf2svg to export the PDFs to other formats.

draw.io

draw.io is a browser-based diagram editor also integrated into jupyter for fun.

Miscellaneous SVG editors

Open source Inkscape can do everything, although I find its Adobe Illustrator pretensions (perhaps unfairly) grating. Aimed firstly at general vector graphic design, which means the functions you want for sciency stuff are not front-and-center, but it can be done.

A fresher option leveraging web technology is Jarosław Foksa’s Boxy.

Just use your programming language

Python, R, julia, javascript all have diverse plotting infrastructure, some of which turns out to also be diagramming infrastructure.

Grammar of graphics

If you really like clever layout, you might enjoy the declarative “compositional layout” diagramming style, as seen in Grammar-of-graphics tools. These do layout like as a kind of algebra of composed styling operations. Compose.jl provides these for Julia. Diagrams is the Haskell version. R’s grid is purportedly somewhat similar for layout, as is all the ggplot2 stuff for style.

PlotDevice

PlotDevice is a cousin of nodebox, which is to say, targeting 2d vector printable outputs.

Pencil

pencil is a fashionable tool for GUI design that happens to be good for some other tricky things, notably flow charts. It’s built as a browser app so has good compatibility with export and presumably some hackability.

Dia

Dia has some neat features; and many confusing ones I can’t imagine the use-case for. Possibly this last one is because I am not in middle management. If you need to produce specialised diagram types for your project manager, Dia probably has the function.

Dia supports more than 30 different diagram types like flowcharts, network diagrams, database models. More than a thousand readymade objects help to draw professional diagrams. Dia can read and write a number of different raster and vector image formats. \[…\] Dia can be scripted and extended using Python.

Crashes on my recent macOS, though, and I can’t be arsed working out why.

Asymptote

Asymptote

Asymptote is a powerful descriptive vector graphics language that provides a natural coordinate-based framework for technical drawing. Labels and equations are typeset with LaTeX, for high-quality PostScript output.

Might be good; haven’t used it. Has a jupyter extension

PGFPlots

PGFPlots is a LaTeX-native diagramming/plotting package which supports PDF output. It is a less awful (although still unwieldy) successor to…

pstricks/tikz

The classic type-your-diagram-in-then-work-out-what-went-wrong option. I like the idea, but the practice, no. Elegant, powerful, and unless you happen to be doing exactly the right kind of diagram, tedious. Doesn’t support PDF output AFAICT.

latexdraw Java pstricks GUI. Might be good, but I couldn’t install the damn thing.

xfig

xfig combines the imprecision of drawing through GUIs, with the abstruseness and fragility of drawing through code. Listed here for the surpassing beauty of its manual page.

Diagrams of probabilistic graphical models

See diagramming graphical models.