Getting Lcapy working on Google Colab with pdflatex and circuitikz

[costajr2019]

Hi everyone,

I ran into a couple of issues while trying to use Lcapy on Google Colab to draw circuits and generate schematics.

The first problem happened when installing LaTeX packages:

!sudo apt-get install texlive-latex-recommended --quiet

I got several 404 Not Found errors for packages such as:

libkpathsea6
libptexenc1
libsynctex2
libtexlua53
libtexluajit2
texlive-binaries

It turned out that Colab was using an outdated package index, so cleaning and updating apt before installation fixed that part.

Then, when trying to draw a circuit in Lcapy, I got:

RuntimeError: circuitikz is not installed

Even after installing LaTeX-related packages, the error continued. In my case, the cause was twofold:

the TeX installation was still incomplete for circuitikz

I had accidentally created a local empty file called circuitikz.sty after a failed wget command, and LaTeX was finding that empty local file first

This sequence worked for me in Google Colab:

!rm -f circuitikz.sty circuitikzgit.sty teste_circuitikz.tex teste_circuitikz.log teste_circuitikz.aux

!sudo apt-get clean
!sudo rm -rf /var/lib/apt/lists/*
!sudo apt-get update -qq
!sudo apt-get install -y texlive texlive-pictures texlive-latex-extra dvipng

!pip install -q --upgrade lcapy

After that, Lcapy was able to draw circuits normally.

For example:
from lcapy import Circuit

a = Circuit("""
V 1 0 step 6; down=1.5
R 1 2 2; right=1.5
C 2 0_2 4; down
W 0 0_2; right
""")

a.draw()

So the key points were:

• clean the apt cache and package lists
• run apt-get update
• install a sufficiently complete TeX Live set
• remove any invalid local circuitikz.sty file
• verify installation with:
  !kpsewhich circuitikz.sty

I hope this helps anyone trying to run Lcapy in Colab.