How do i get the bars lined up together?

📊 Plotly Python
1

Hey Guys, I was making a grouped bar chart using plotly. I set the width of each bar to 0.2 and the gargap and bargroupgap as 0 but im still getting a lot of space between the bars of each group. I would like the charts in each category to be next to each other. Does any one know how to do it? in the attached photo, the blue and red bars should be next to each other.

Thanks

image
image1494×561 2.61 KB

2

The default grouped bar chart should actually look as you described. How do you create the shown chart code wise?

3

the default bar chart was what i needed but the width of the bars was too thick. i adjusted the width to myu requirements and they simply drifted apart.
Code wise, the bar is almost exactly the same as the example in the documentation except for the width as 0.2 and the update layout with bargap=0 and bargroupgap = 0.

fig = go.Figure(
data=[
go.Bar(
name=“apple”,
x=categories,
y=[20, 14, 23],
width=0.2,
marker_color=“#ffc82c”,
),
go.Bar(
name=“orange”,
x=categories,
y=[12, 18, 29],
width=0.2,
marker_color=“#173a64”,
),
]
)

Change the bar mode

fig.update_layout(barmode=“group”)
fig.update_layout(
bargap=0.0, # gap between bars of adjacent location coordinates.
bargroupgap=0, # gap between bars of the same location coordinate.
plot_bgcolor=“white”,
)

4

This is how I do it:

To change bar gap : fig.update_traces(width=0.4)

import plotly.graph_objects as go
import plotly.express as pc
from plotly.subplots import make_subplots
import pandas as pd

#
data = {
    'Cat': ['Cat A', 'Cat B', 'Cat C', 'Cat A', 'Cat B', 'Cat C'],
    'Group': ['Group A', 'Group A', 'Group A', 'Group B', 'Group B', 'Group B'],
    'Value': [10, 15, 20, 25, 30, 35]
}

df = pd.DataFrame(data)

# Define unique groups

unique_groups = df['Group'].unique()
n_groups = len(unique_groups)

#create color map
color_map= dict(
    zip(
    unique_groups, px.colors.qualitative.Set3[:n_groups]
         )
    )

#create subplots
fig = make_subplots(
    rows=1,
    cols=len(unique_groups),
    shared_yaxes=True,
    shared_xaxes=True,
    horizontal_spacing=0,
    x_title='x_axis',
    y_title='y_axis'  # Updated to 'y_axis'
)

#loop through groups and add them as subplots
for index, group in enumerate(unique_groups):
    col_number = index + 1

    fig.append_trace(go.Bar(
        x=df[df['Group'] == group]['Cat'],  
        y=df[df['Group'] == group]['Value'], 
        marker_color=color_map[group], 
        name=group
    ), row=1, col=col_number)

fig.update_traces(width=0.4)  

for i in range(1, n_groups + 1):
    axis_name = f'yaxis{i}' if i == 1 else f'yaxis{i}'
    fig.update_layout({
        axis_name: dict(
            showgrid=True,
            gridcolor='rgba(0, 0, 0, 0.3)'
        )
    })
 
fig.update_layout(
    plot_bgcolor='rgba(0,0,0,0)',
    #paper_bgcolor='rgba(0,0,0,0)' #transparent background
    )

#fig.write_image("fig1.png", scale=3)

fig.show()

plot-2
plot-21281×450 12.5 KB

Or I use the histogram without the histfunc when suitable:


import plotly.express as px
import pandas as pd

groups = ['Group A', 'Group A', 'Group A', 'Group B', 'Group B', 'Group B']
years = [2019, 2020, 2021, 2019, 2020, 2021]
values = [45, 60, 75, 30, 55, 70]


data = {'Group': groups, 'Year': years, 'Value': values}
dff = pd.DataFrame(data)

fig = px.histogram(dff, x='Group', y='Value', color='Year',
                   barmode='group', histfunc=None,
                   color_discrete_sequence=px.colors.qualitative.Set3,
                   category_orders={'Group': ['Group A', 'Group B']}
                   )

fig.update_layout(
    plot_bgcolor='rgba(0,0,0,0)',
    #paper_bgcolor='rgba(0,0,0,0)' #transparent background
    )
fig.update_yaxes(gridcolor='rgba(0, 0, 0, 0.3)')

fig.show()

hist
hist1281×450 14.1 KB