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Gantt Charts in Python

How to make Gantt Charts in Python with Plotly. Gantt Charts use horizontal bars to represent the start and end times of tasks.


New to Plotly?

Plotly is a free and open-source graphing library for Python. We recommend you read our Getting Started guide for the latest installation or upgrade instructions, then move on to our Plotly Fundamentals tutorials or dive straight in to some Basic Charts tutorials.

A Gantt chart is a type of bar chart that illustrates a project schedule. The chart lists the tasks to be performed on the vertical axis, and time intervals on the horizontal axis. The width of the horizontal bars in the graph shows the duration of each activity.

Gantt charts can be made using a figure factory as detailed in this page. See also the bar charts examples.

Simple Gantt Chart

In [1]:
import plotly.figure_factory as ff

df = [dict(Task="Job A", Start='2009-01-01', Finish='2009-02-28'),
      dict(Task="Job B", Start='2009-03-05', Finish='2009-04-15'),
      dict(Task="Job C", Start='2009-02-20', Finish='2009-05-30')]

fig = ff.create_gantt(df)
fig.show()

Index by Numeric Variable

In [2]:
import plotly.figure_factory as ff

df = [dict(Task="Job A", Start='2009-01-01', Finish='2009-02-28', Complete=10),
      dict(Task="Job B", Start='2008-12-05', Finish='2009-04-15', Complete=60),
      dict(Task="Job C", Start='2009-02-20', Finish='2009-05-30', Complete=95)]

fig = ff.create_gantt(df, colors='Viridis', index_col='Complete', show_colorbar=True)
fig.show()

Index by String Variable

In [3]:
import plotly.figure_factory as ff

df = [dict(Task="Job A", Start='2009-01-01', Finish='2009-02-01', Resource='Apple'),
      dict(Task="Job B", Start='2009-03-05', Finish='2009-04-15', Resource='Grape'),
      dict(Task="Job C", Start='2009-04-20', Finish='2009-09-30', Resource='Banana')]

colors = ['#7a0504', (0.2, 0.7, 0.3), 'rgb(210, 60, 180)']

fig = ff.create_gantt(df, colors=colors, index_col='Resource', reverse_colors=True,
                      show_colorbar=True)
fig.show()

Use a Dictionary for Colors

In [4]:
import plotly.figure_factory as ff

df = [dict(Task="Job A", Start='2016-01-01', Finish='2016-01-02', Resource='Apple'),
      dict(Task="Job B", Start='2016-01-02', Finish='2016-01-04', Resource='Grape'),
      dict(Task="Job C", Start='2016-01-02', Finish='2016-01-03', Resource='Banana')]

colors = dict(Apple='rgb(220, 0, 0)', Grape='rgb(170, 14, 200)', Banana=(1, 0.9, 0.16))

fig = ff.create_gantt(df, colors=colors, index_col='Resource', show_colorbar=True)
fig.show()

Use a Pandas Dataframe

In [5]:
import plotly.figure_factory as ff

import pandas as pd
df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/gantt_example.csv')

fig = ff.create_gantt(df, colors=['#333F44', '#93e4c1'], index_col='Complete',
                      show_colorbar=True, bar_width=0.2, showgrid_x=True, showgrid_y=True)
fig.show()

Using Hours and Minutes in Times

In [6]:
import plotly.figure_factory as ff

df = [
    dict(Task='Morning Sleep', Start='2016-01-01', Finish='2016-01-01 6:00:00', Resource='Sleep'),
    dict(Task='Breakfast', Start='2016-01-01 7:00:00', Finish='2016-01-01 7:30:00', Resource='Food'),
    dict(Task='Work', Start='2016-01-01 9:00:00', Finish='2016-01-01 11:25:00', Resource='Brain'),
    dict(Task='Break', Start='2016-01-01 11:30:00', Finish='2016-01-01 12:00:00', Resource='Rest'),
    dict(Task='Lunch', Start='2016-01-01 12:00:00', Finish='2016-01-01 13:00:00', Resource='Food'),
    dict(Task='Work', Start='2016-01-01 13:00:00', Finish='2016-01-01 17:00:00', Resource='Brain'),
    dict(Task='Exercise', Start='2016-01-01 17:30:00', Finish='2016-01-01 18:30:00', Resource='Cardio'),
    dict(Task='Post Workout Rest', Start='2016-01-01 18:30:00', Finish='2016-01-01 19:00:00', Resource='Rest'),
    dict(Task='Dinner', Start='2016-01-01 19:00:00', Finish='2016-01-01 20:00:00', Resource='Food'),
    dict(Task='Evening Sleep', Start='2016-01-01 21:00:00', Finish='2016-01-01 23:59:00', Resource='Sleep')
]

colors = dict(Cardio = 'rgb(46, 137, 205)',
              Food = 'rgb(114, 44, 121)',
              Sleep = 'rgb(198, 47, 105)',
              Brain = 'rgb(58, 149, 136)',
              Rest = 'rgb(107, 127, 135)')

fig = ff.create_gantt(df, colors=colors, index_col='Resource', title='Daily Schedule',
                      show_colorbar=True, bar_width=0.8, showgrid_x=True, showgrid_y=True)
fig.show()

Group Tasks Together

In [7]:
import plotly.figure_factory as ff

df = [dict(Task="Job-1", Start='2017-01-01', Finish='2017-02-02', Resource='Complete'),
      dict(Task="Job-1", Start='2017-02-15', Finish='2017-03-15', Resource='Incomplete'),
      dict(Task="Job-2", Start='2017-01-17', Finish='2017-02-17', Resource='Not Started'),
      dict(Task="Job-2", Start='2017-01-17', Finish='2017-02-17', Resource='Complete'),
      dict(Task="Job-3", Start='2017-03-10', Finish='2017-03-20', Resource='Not Started'),
      dict(Task="Job-3", Start='2017-04-01', Finish='2017-04-20', Resource='Not Started'),
      dict(Task="Job-3", Start='2017-05-18', Finish='2017-06-18', Resource='Not Started'),
      dict(Task="Job-4", Start='2017-01-14', Finish='2017-03-14', Resource='Complete')]

colors = {'Not Started': 'rgb(220, 0, 0)',
          'Incomplete': (1, 0.9, 0.16),
          'Complete': 'rgb(0, 255, 100)'}

fig = ff.create_gantt(df, colors=colors, index_col='Resource', show_colorbar=True,
                      group_tasks=True)
fig.show()

Reference

For more info on ff.create_gantt(), see the full function reference

What About Dash?

Dash is an open-source framework for building analytical applications, with no Javascript required, and it is tightly integrated with the Plotly graphing library.

Learn about how to install Dash at https://dash.plot.ly/installation.

Everywhere in this page that you see fig.show(), you can display the same figure in a Dash application by passing it to the figure argument of the Graph component from the built-in dash_core_components package like this:

import plotly.graph_objects as go # or plotly.express as px
fig = go.Figure() # or any Plotly Express function e.g. px.bar(...)
# fig.add_trace( ... )
# fig.update_layout( ... )

import dash
import dash_core_components as dcc
import dash_html_components as html

app = dash.Dash()
app.layout = html.Div([
    dcc.Graph(figure=fig)
])

app.run_server(debug=True, use_reloader=False)  # Turn off reloader if inside Jupyter