Skip to content
Related Articles

Related Articles

Improve Article
Save Article
Like Article

Create Heatmaps using graph_objects class in Plotly

  • Last Updated : 05 Sep, 2020

A Plotly is a Python library that is used to design graphs, especially interactive graphs. It can plot various graphs and charts like histogram, barplot, boxplot, spreadplot, and many more. It is mainly used in data analysis as well as financial analysis. plotly is an interactive visualization library.

Heatmaps using graph_objects

A heatmap is a two-dimensional graphical representation of data where the individual values that are contained in a matrix are represented as colors.

 Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.  

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning - Basic Level Course

Syntax: plotly.graph_objects.Heatmap(arg=None, autocolorscale=None, colorbar=None, colorscale=None, x=None, y=None, z=None, **kwargs)



Parameters:

arg: dict of properties compatible with this constructor

autocolorscale: Determines whether the colorscale is a default palette (autocolorscale: true) or the palette determined by colorscale. 

colorbar: plotly.graph_objects.heatmap.ColorBar instance or dict with compatible properties

colorscale: Sets the colorscale. The colorscale must be an array containing arrays mapping a normalized value to an rgb, rgba, hex, hsl, hsv, or named color string.

x: Sets the x coordinates.

y: Sets the y coordinates.

z: Sets the z coordinates.



Example:

Python3




import plotly.graph_objects as go
  
feature_x = np.arange(0, 50, 2
feature_y = np.arange(0, 50, 3
  
# Creating 2-D grid of features 
[X, Y] = np.meshgrid(feature_x, feature_y) 
  
Z = np.cos(X / 2) + np.sin(Y / 4
  
fig = go.Figure(data =
     go.Heatmap(x = feature_x, y = feature_y, z = Z,))
  
fig.show()


Output:

Presenting Heat map with Unequal Block Sizes

In plotly, it is possible to show the unequal sizes of the blocks as to make the data differentiate between each other to make it more clear while presenting as the data has different height and width compared to each other.

Example:

Python3




import plotly.graph_objects as go
  
feature_x = np.arange(0, 50, 2)
feature_y = np.arange(0, 50, 3)
  
# Creating 2-D grid of features
[X, Y] = np.meshgrid(feature_x, feature_y)
  
Z = np.cos(X / 2) + np.sin(Y / 4)
  
fig = go.Figure(data=go.Heatmap(
  x=feature_x, y=feature_y, z=Z,))
  
fig.update_layout(
    margin=dict(t=200, r=200, b=200, l=200),
    showlegend=False,
    width=700, height=700,
    autosize=False)
  
  
fig.show()


Output:




My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!