Matplotlib Marker Fill

Matplotlib Marker Fill

This explanation will look at how to customize marker style, create a filled marker, and create a plot with different line styles in Matplotlib.

Create Filled and Unfilled Marker in Matplotlib

The marker represents the points on a graph. It can be a single character string or an integer number.

We can customize marker style and size using these two parameters, the first one is a marker and the second one is markersize. The marker has several styles to point out on graphs.

Value Description
9 An integer number 9 will mark the data points using the triangles pointing to the right.
+ A string with a + character will mark the data points using the + sign.
x A string with the lowercase letter x will mark the data points using unfilled crosses.
X A string with an uppercase letter X will mark the data points using filled crosses.
4 An integer number 4 will mark the data points using the triangles pointing to the left.
s A string with the lowercase letter s will mark the data points using squares.
d A string with the lowercase letter d will mark the data points using diamonds.
P A string with an uppercase letter P will mark the data points using filled plus signs.
p A string with the lowercase letter p will mark the data points using polygons.
h A string with the lowercase letter h will mark the data points using hexagons.
H A string with an uppercase letter H will mark the data points using filled hexagons.
o A string with the lowercase letter o will mark the data points using owl shapes.

Let’s see an example that uses line colors, styles, and markers.

We need to import numpy, and We also need to import matplotlib.pyplot. Next, we create the data arrays, where X contains 15 points evenly distributed between negative pi and positive pi, and the C contains the cosine values of X and S contains the sine values of X.

import numpy as np
import matplotlib.pyplot as plot

X=np.linspace(-np.pi,np.pi,15)
C=np.cos(X)
S=np.sin(X)

Then, let’s create a figure with a figsize is 5 inches by 4 inches and a dpi is 80. We need to create four axes using the subplot function with 2 rows and 2 columns.

In the first axes, we plot the cosine function. The line color is navy, the linestyle is a densely dashed line, the marker is a star, and the markersize is 8.

plot.subplot(2,2,1)
plot.plot(X,C,color="navy",linestyle=(0,(5,1)),marker="*",markersize=8)

In the second axes, we plot the sine function. The line color is "orangered", the marker is a cross, and the markersize is 8.

plot.subplot(2,2,2)
plot.plot(X,S,color="orangered",linestyle=(0,(3,1,1,1)),marker="x",markersize=8)

In the third axes, we plot the negative cosine function. The line color is "darkgreen", the linestyle is a solid line, the marker is a circle, and the marker size is 8.

plot.subplot(2,2,3)
plot.plot(X,-C,color="darkgreen",linestyle=(0,()),marker="o",markersize=8)

In the fourth axes, we plot the negative sine function. The line color is firebrick, and the linestyle is a densely dotted line, the marker is a plus sign, and the marker size is 8.

plot.subplot(2,2,4)
plot.plot(X,-S,color="firebrick",linestyle=(0,(1,1)),marker="p",markersize=8)

Full Source Code:

import numpy as np
import matplotlib.pyplot as plot

X=np.linspace(-np.pi,np.pi,15)
C=np.cos(X)
S=np.sin(X)
fig=plot.figure(figsize=(5,4),dpi=80)

plot.subplot(2,2,1)
plot.title("Unfilled Marker")
plot.plot(X,C,color="navy",linestyle=(0,(5,1)),marker="*",markersize=8)
plot.subplot(2,2,2)
plot.plot(X,S,color="orangered",linestyle=(0,(3,1,1,1)),marker="x",markersize=8)
plot.subplot(2,2,3)
plot.plot(X,-C,color="darkgreen",linestyle=(0,()),marker="o",markersize=8)
plot.subplot(2,2,4)
plot.plot(X,-S,color="firebrick",linestyle=(0,(1,1)),marker="p",markersize=8)
plot.show()

Output:

unfilled marker in matplotlib

The following is an example of filling markers with different characters.

Code:

import numpy as np
import matplotlib.pyplot as plot

X=np.linspace(-np.pi,np.pi,15)
C=np.cos(X)
S=np.sin(X)
fig=plot.figure(figsize=(5,4),dpi=80)

plot.subplot(2,2,1)
plot.title("Filled Marker")
plot.plot(X,C,color="navy",linestyle=(0,(5,1)),marker="D",markersize=8)
plot.subplot(2,2,2)
plot.plot(X,S,color="orangered",linestyle=(0,(3,1,1,1)),marker="X",markersize=8)
plot.subplot(2,2,3)
plot.plot(X,-C,color="darkgreen",linestyle=(0,()),marker="P",markersize=8)
plot.subplot(2,2,4)
plot.plot(X,-S,color="firebrick",linestyle=(0,(1,1)),marker="H",markersize=8)
plot.show()

Output:

filled marker in matplotlib

Click here to read more about filled and unfilled marker styles.

Salman Mehmood avatar Salman Mehmood avatar

Hello! I am Salman Bin Mehmood(Baum), a software developer and I help organizations, address complex problems. My expertise lies within back-end, data science and machine learning. I am a lifelong learner, currently working on metaverse, and enrolled in a course building an AI application with python. I love solving problems and developing bug-free software for people. I write content related to python and hot Technologies.

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