Handcalcs

Introduction

This is a package for generating LaTeX maths and designed to improve documentation for your calculations. This package was designed to work in both Jupyter and Pluto.jl.

This package supplies macros to generate \LaTeX formatted strings from mathmatical formulas. This package takes inspiration from handcalcs.py which is a python package that works best in jupyter notebooks. The goal is to get the functionalities of that package and bring them to Julia. At this point, I believe most (if not all) of the features from the python package are here. The package integrates well with Unitful.jl. This package is an extension of Latexify.jl. The @latexdefine macro is similar to the main @handcalcs macro, but instead of only a symbolic rendering it also renders the numeric substitution.

Note: This package now renders properly in Quarto/Weave!! You can change the default settings to your liking. See docs for more info.

Basic Demo

Note: In the gif, @handfunc is used for unrolling a function with algebraic expressions. It is now recommended to use the @handcalcs macro for this. See the docs.

Basic example:

Single line expression

using Handcalcs
a = 3
b = 4
@handcalcs c = sqrt(a^2 + b^2)

or

@handcalcs begin c = sqrt(a^2 + b^2) end

You may want to do the latter in Pluto. This will supress the assignment callout in the top left of the output cell.

This generates a LaTeXString (from LaTeXStrings.jl) which, when printed looks like:

$c = \sqrt{a^{2} + b^{2}} = \sqrt{3^{2} + 4^{2}} = 5.0$

And when this LaTeXString is displayed in an environment which supports the tex/latex MIME type (Jupyter and Pluto notebooks, Jupyterlab and Hydrogen for Atom) it will automatically render as:

Also note c is evaluated as well.

Multi line expression

You can add comments to the side of the expression by adding a string beside the expression. Note: the variables being assigned in the expressions are evaluated (see docs for more details). See example below.

a = 2
b = 5
@handcalcs begin 
    c = a + b; "eq 1";
    d = a - c
end

$\begin{aligned}
c &= a + b = 2 + 5 = 7\;\text{  }(\text{eq 1})
\\[10pt]
d &= a - c = 2 - 7 = -5
\end{aligned}$

Function expression

This macro will generate LaTeX for a function that was called. The generated LaTeX would be the algebraic equations within the function.

b = 5
h = 15
@handcalcs Iy = calc_Ix(b, h) # calc_Ix is some function defined in another package

$\begin{aligned}
Ix &= \frac{b \cdot h^{3}}{12} = \frac{5 \cdot 15^{3}}{12} = 1406.25
\end{aligned}$

Note that Iy is evaluated (notIx). Also note that return statements are filtered out of the function body, so keep relevant parts separate from return statements.

Set default precision

Currently, to set the default precision, use the set_default function in combination with the Format.jl package. The set_default function is re-exported from the Latexify.jl package. See here for more Latexify default settings. This is what I primarily use for now (you can see the use in the gif above):

using Format
set_default(fmt = x->format(round(x, digits=4)))

Installation

This package is registered in the Julia registry, so to install it you can just run:

Pkg.add("Handcalcs")

Further information

For further information see the docs