Maths.md

Charts & graphs

Charts

Using Matplotlib

Before running this example, please install the required dependencies using the command below:

pip install fpdf2 matplotlib

Example taken from Matplotlib artist tutorial:

{% include "../tutorial/matplotlib_demo.py" %}

Result:

You can also embed a figure as SVG:

from fpdf import FPDF
import matplotlib.pyplot as plt
import numpy as np

plt.figure(figsize=[2, 2])
x = np.arange(0, 10, 0.00001)
y = x*np.sin(2* np.pi * x)
plt.plot(y)
plt.savefig("figure.svg", format="svg")

pdf = FPDF()
pdf.add_page()
pdf.image("figure.svg")
pdf.output("doc-with-figure.pdf")

Using Pandas

The dependencies required for the following examples can be installed using this command:

pip install fpdf2 matplotlib pandas

Create a plot using pandas.DataFrame.plot:

{% include "../tutorial/matplotlib_pandas.py" %}

Result:

Create a table with pandas DataFrame:

{% include "../tutorial/matplotlib_pandas_df.py" %}

Result:

Using Plotly

Before running this example, please install the required dependencies using the command below:

pip install fpdf2 plotly kaleido numpy

kaleido is a cross-platform library for generating static images that is used by plotly.

Example taken from Plotly static image export tutorial:

{% include "../tutorial/plotly_demo.py" %}

Result:

You can also embed a figure as SVG but this is not recommended because the text data such as the x and y axis bars might not show as illustrated in the result image because plotly places this data in a svg text tag which is currently not supported by FPDF2.

Before running this example, please install the required dependencies:

pip install fpdf2 plotly kaleido pandas

{% include "../tutorial/plotly_svg.py" %}

Result:

Using Pygal

Pygal is a Python graph plotting library. You can install it using: pip install pygal

fpdf2 can embed graphs and charts generated using Pygal library. However, they cannot be embedded as SVG directly, because Pygal inserts <style> & <script> tags in the images it produces (cf. pygal/svg.py), which is currently not supported by fpdf2. The full list of supported & unsupported SVG features can be found there: SVG page.

You can find documentation on how to convert vector images (SVG) to raster images (PNG, JPG), with a practical example of embedding PyGal charts, there: SVG page.

Mathematical formulas

fpdf2 can only insert mathematical formula in the form of images. The following sections will explaing how to generate and embed such images.

Using Google Charts API

Official documentation: Google Charts Infographics - Mathematical Formulas.

Example:

{% include "../tutorial/equation_google_charts.py" %}

Result:

Using LaTeX & Matplotlib

Matplotlib can render LaTeX: Text rendering With LaTeX.

Example:

{% include "../tutorial/equation_matplotlib.py" %}

Result:

If you have trouble with the SVG export, you can also render the matplotlib figure as pixels:

{% include "../tutorial/equation_matplotlib_raster.py" %}