Saving figures to files in Matplotlib - Cheat Sheet & Quick Revision

Recall & Review

beginner

What function in matplotlib do you use to save a figure to a file?

You use plt.savefig() to save the current figure to a file.

beginner

How do you save a figure as a PNG file named 'plot.png'?

Use plt.savefig('plot.png') to save the figure as a PNG file named 'plot.png'.

intermediate

What parameter do you use in savefig() to set the resolution of the saved image?

Use the dpi parameter to set the resolution, for example plt.savefig('plot.png', dpi=300).

beginner

True or False: You must call plt.show() before plt.savefig() to save the figure.

False. You should call plt.savefig() before plt.show() because plt.show() can clear the figure.

intermediate

How can you save a figure in vector format using matplotlib?

Save the figure as a PDF or SVG by using the file extension in savefig(), for example plt.savefig('plot.pdf') or plt.savefig('plot.svg').

Which command saves the current matplotlib figure as a JPEG file named 'image.jpg'?

A plt.save('image.jpg')

B plt.savefig('image.jpg')

C plt.savefig('image.png')

D plt.export('image.jpg')

plt.savefig() is the correct function to save figures. The filename extension determines the format.

What does the dpi parameter control in plt.savefig()?

A The resolution (dots per inch) of the saved image

B The size of the figure in inches

C The color of the figure background

D The file format of the saved image

dpi sets the resolution, higher dpi means better image quality.

If you want to save a figure as a vector graphic, which file extension should you use?

A .png

B .jpg

C .bmp

D .svg

SVG is a vector graphic format. PDF also works for vector graphics.

When should you call plt.savefig() in your code?

A Before <code>plt.show()</code>

B Only if you want to display the figure

C It does not matter

D After <code>plt.show()</code>

Call plt.savefig() before plt.show() because plt.show() can clear the figure.

Which of these is NOT a valid file format for plt.savefig()?

A .png

B .pdf

C .exe

D .svg

.exe is an executable file, not an image format.

Explain how to save a matplotlib figure to a file with high resolution.

Think about the function name and the dpi setting.

Describe the difference between saving a figure as PNG and SVG in matplotlib.

Consider image quality and scaling.