[Fixed]-Matplotlib svg as string and not a file

by

23👍

✅

Try using StringIO to avoid writing any file-like object to disk.

import matplotlib.pyplot as plt
import StringIO
from matplotlib import numpy as np

x = np.arange(0,np.pi*3,.1)
y = np.sin(x)

fig = plt.figure()
plt.plot(x,y)

imgdata = StringIO.StringIO()
fig.savefig(imgdata, format='svg')
imgdata.seek(0)  # rewind the data

svg_dta = imgdata.buf  # this is svg data

file('test.htm', 'w').write(svg_dta)  # test it
👤Paul

7👍

Here is python3 version

import matplotlib.pyplot as plt
import numpy as np
import io

f = io.BytesIO()
a = np.random.rand(10)
plt.bar(range(len(a)), a)
plt.savefig(f, format = "svg")

print(f.getvalue()) # svg string
👤abasar

0👍

Based on abasar’s answer, I propose the following snippet:

from io import StringIO
import matplotlib.pyplot as plt

def plot_to_svg() -> str:
    """
    Saves the last plot made using ``matplotlib.pyplot`` to a SVG string.
    
    Returns:
        The corresponding SVG string.
    """
    s = StringIO()
    plt.savefig(s, format="svg")
    plt.close()  # https://stackoverflow.com/a/18718162/14851404
    return s.getvalue()

a = [10, 20, 5]
plt.bar(range(len(a)), a)
svg = plot_to_svg()
print(svg)
👤mando

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