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harpertutorial - Plotting Graphs
HarperframeInc (235)

Plotting Graphs...

You do that in math, science, and in python too!
First, we need to import matplotlib


NOTE
matplotlib is a looooong name. Use as mpl instead.
I will be referring to it as mpl.


So, what's next?
Let's start your first simple graph.

# DON'T EVER USE:
import matplotlib as mpl
# ALWAYS USE:
import matplotlib.pyplot as mpl

So we imported mpl. What's next?
We can create a line graph with:

import matplotlib.pyplot as mpl
mpl.plot([1, 2, 3, 4], [1, 4, 9, 16])

Doing this will give us:

Do you like it?
Mess around with it, do whatever you want!

Labeling

Labels, Labels, Labels.
Your X axis, your Y axis.
You can label your X & Y axis with:

import matplotlib.pyplot as mpl
mpl.plot([1, 2, 3, 4], [1, 4, 9, 16])
mpl.xlabel("X Label")
mpl.ylabel("Y Label")

Here's an example the Pyplot Guide gives:

Saving and Showing.

You can show with the:

mpl.show()

Or you want to download it,

mpl.save()

Bonus

Eww, I hate that blue line. Why is it there?
Well,

plt.plot([1, 2, 3, 4], [1, 4, 9, 16], 'ro')

Gives you...
Drumroll Please....

Wow!
The blue line is because all graphs default to "-b"
How about the red circles? Its "ro"
How about all colors and shapes?
Here's what the guide has to say.

Colors
The following color abbreviations are supported:
'b' blue
'g' green
'r' red
'c' cyan
'm' magenta
'y' yellow
'k' black
'w' white
Markers
'.' point marker
',' pixel marker
'o' circle marker
'v' triangledown marker
'^' triangle_up marker
'<' triangle_left marker
'>' triangle_right marker
'1' tri_down marker
'2' tri_up marker
'3' tri_left marker
'4' tri_right marker
's' square marker
'p' pentagon marker
'*' star marker
'h' hexagon1 marker
'H' hexagon2 marker
'+' plus marker
'x' x marker
'D' diamond marker
'd' thin_diamond marker
'|' vline marker
'
' hline marker
Line Styles
'-' solid line style
'--' dashed line style
'-.' dash-dot line style
':' dotted line style
Please don't ask me questions about this, because I literally have no clue on shapes and stuff, I can help with anything else. Here's the guide on the plot() function: https://matplotlib.org/api/_as_gen/matplotlib.pyplot.plot.html#matplotlib.pyplot.plot

Liked this tutorial? Was it anyway helpful to you? If so, please upvote this tutorial. I might be adding on more soon.

The Guide: https://matplotlib.org/tutorials/introductory/pyplot.html#sphx-glr-tutorials-introductory-pyplot-py
Use the code below for reference

Commentshotnewtop
timmy_i_chen (988)

Awesome - thanks for making this!