The Scatter plot is a type of plot that is used to show the data as a collection of points.
- This plot is mainly used to observe the relationship between the two variables.
- Scatter plots make use of dots to represent the relationship between two variables.
- These plots are mainly used to plot data points on the horizontal and vertical axis in order to show how much one variable is affected by another.
- In 2-Dimensions it is used to compare two variables while in 3-Dimensions it is used to make comparisons in three variables.
Matplotlib scatter()
Function
The method scatter()
in the pyplot module in matplotlib library of Python is mainly used to draw a scatter plot.
The syntax to use this method is given below:
matplotlib.pyplot.scatter(x_axis_data, y_axis_data, s, c, marker, cmap, vmin, vmax,alpha,linewidths, edgecolors)
Function Parameters:
Let us discuss the parameters of scatter()
method:
- x_axis_dataThis parameter indicates an array containing x-axis data.
- y_axis_dataThis parameter indicates an array containing y-axis data.
- s<This parameter indicates the marker size (it can be scalar or array of size equal to the size of x or y). It is an optional parameter and the default value is
None
. - cThis parameter indicates the color of sequence and it is an optional parameter with default value equals to
None
. - markerThis parameter is used to indicate the marker style. The default value of this parameter is
None
and it is also an optional parameter. - cmapThis optional parameter indicates cmap name with default value equals to
None
. - linewidthsThis parameter indicates the width of the marker border and having
None
as default value. - edgecolorsThis parameter is used to indicate the marker border-color and also it’s default value is
None
. - alphaThis option indicates the blending value, between 0 (transparent) and 1 (opaque).
Let us dive into some examples and create some scatter plots.
Simple Scatter Plot Example:
Below we have a code snippet to create a simple scatter plot. Let us go through the code snippet:
import matplotlib.pyplot as plt
x =[5, 7, 8, 7, 2, 17, 2, 9, 4, 11, 12, 9, 6]
y =[99, 86, 87, 88, 100, 86, 103, 87, 94, 78, 77, 85, 86]
plt.scatter(x, y, c ="red")
plt.show()
When you run the above code on your machine you will see the output as shown below:

Scatter Plot with large Dataset:
Let us create another scatter plot with different random numbers and the code snippet is given below:
import numpy as np
import matplotlib.pyplot as plt
# Creating the data
N = 1000
x = np.random.rand(N)
y = np.random.rand(N)
colors = (0,0,0)
area = np.pi*3
plt.scatter(x, y, s=area, c=colors, alpha=0.5)
plt.title('Scatter plot studytonight.com')
plt.xlabel('x')
plt.ylabel('y')
plt.show()
The output for the same is as follows: