Issue in Latex writing in ROOT plot

[gpadovan]

Hi, I want to draw the LaTeX \ell on a plot done by ROOT.

Following the convention in which the backslash is substituted with “#” before LaTeX syntax I wrote:

y_title["VLQ_GEN_zp33LL"] = "#sqrt{#zeta_{q} #zeta_{#ell}}"

However this is failing, see the attached figure, while the syntax for the other commands (e.g. #sqrt, #zeta) is working. Can you give any help?

Thanks, best,
Giovanni Padovano

---

I run with:

python3 contour_plot.py -o /afs/cern.ch/user/g/gpadovan/eos/www/ongoing/2025-01-27_unblinded-limits/

The command:

python3 --version

yields:

Python 3.9.21

The command:

root --version

yields:

ROOT Version: 6.34.02

Built for linuxx8664gcc on Jan 15 2025, 00:00:00

From tags/6-34-02@6-34-02

[yus]

Hi Giovanni,
try \\ell instead of #ell.

[gpadovan]

Hi,

the string

y_title["VLQ_GEN_zp33LL"] = "#sqrt{#zeta_{q} #zeta_{\\ell}}"

yields different results in .png and .pdf (this is quite strange!)

In the .png I get this (the string is messed up):

In the .pdf I get this (no variation):

Is there anything els I can do?

Thanks,
Giovanni

[yus]

Yeah, I don’t think the \\ell thing is supposed to work in PDFs unfortunately, see the latest replies at \ell symbol in PDF and \ell symbol in TH1 axis.
For the PNG, try replacing all # with \\.

[couet]

ell is supported only by TMathText and TMathText is not supported by TPdf. You might consider using web graphics.