How to use superscript characters (Latex?) with fpdf2 python?

Question

I hope you are well.

I'm trying to write the following to a pdf using the fpdf2 library:

GHI (kWh $m^-2 day^{-1}$)

But I'm not getting the expected result, the text is written in the pdf in the same way as the code, that is: GHI (kWh $m^-2 day^{-1}$)

Here is a basic example:

from fpdf import FPDF
pdf = FPDF()
pdf.add_page()
pdf.set_font("helvetica", "B", 16)
pdf.cell(40, 10, r"GHI (kWh $m^-2 day^{-1}$)")
pdf.output("test.pdf")

Could someone let me know how I can write this text in the pdf so that it is rendered correctly?

Thank you very much in advance,

Robson

Answer 1

fpdf2 now supports subscript & superscript, as well as <sub> & <sup> HTML tags: https://github.com/PyFPDF/fpdf2/blob/master/CHANGELOG.md#added-1

You can also render mathematical formulas using Google Charts API or Matplotlib: https://pyfpdf.github.io/fpdf2/Maths.html#mathematical-formulas

from io import BytesIO
from urllib.parse import quote
from urllib.request import urlopen
from fpdf import FPDF

formula = r"GHI (kWh $m^-2 day^{-1}$)"
height = 170
url = f"https://chart.googleapis.com/chart?cht=tx&chs={height}&chl={quote(formula)}"
with urlopen(url) as img_file:
    img = BytesIO(img_file.read())

pdf = FPDF()
pdf.add_page()
pdf.image(img, w=30)
pdf.output("equation-with-gcharts.pdf")