Add custom color to marker color for each year in a px.bar graph

📊 Plotly Python
1

I am trying to assign a custom colour to my Plotly Express Bar graph
I create the plot fine and it displays the data as I would like it. It just won’t allow me to specify the colours for the bars.

correct-plot-wrong-colors
correct-plot-wrong-colors983×800 19.8 KB

If I try

fig.update_traces(marker_color=['#071633', '#0DEFFF'], showlegend=False)

I get the following plot which is the right colours just not on the correct bars

wrong
wrong983×800 19.8 KB

Can someone help me with assigning the colour #071633 to 2019 and #0DEFFF to 2020

My complete code for the chart creating and data is as follows.


# Our imaginary Data to be used to create our Pandas Series
dict_2019 = {'Legal' : 70,
           'Police' : 90,
           'Government' : 0, 
           'Army' : 70,
           'Navy' : 58,
           'Air Force' : 25,
           'Coastguard' : 0,
           'Ambulance' : 6,
           'Counter-Terror' : 39,
           'Direct Action' : 12
          }

dict_2020 = {'Legal' : 95,
           'Police' : 50,
           'Government' : 24,
           'Army' : 95,
           'Navy' : 0,
           'Air Force' : 65,
           'Coastguard' : 0,
           'Ambulance' : 0,
           'Counter-Terror' : 49,
           'Direct Action' : 25
          }

# Create our Pandas Series
sf1 = pd.Series(dict_2019)
sf2 = pd.Series(dict_2020)

# Merge our Pandas Series
df_merge = pd.concat([sf1, sf2], axis = 1)

# Create our column names
df_merge.set_axis(column_names, axis = 'columns', inplace=True)

# Assign our new column names to the df_merge dataframe
df_merge.set_axis(column_names, axis = 'columns', inplace=True)

# Create our boolean mask
action_mask = (df_merge['2019'] > 0) & (df_merge['2020'] > 0)

# Draw our Plot
fig = px.bar(df_merge[action_mask])

# Change the bar mode
fig.update_layout(barmode='group',
                  title='<b>Number of actions by unit<b>',
                  xaxis_categoryorder = 'category ascending',
                  height = 800,
                  plot_bgcolor='rgba(0,0,0,0)',
                  showlegend=True
                 )

fig.update_traces(marker_color=['#071633', '#0DEFFF'], showlegend=True)

fig.update_xaxes(tickangle=45,
                 title_text='<b>Unit<b>',
                 showline=True,
                 linewidth=1,
                 linecolor='#071633'
                )

fig.update_yaxes(title_text='<b>Count<b>',
                 showline=True,
                 linewidth=0.25,
                 linecolor='#071633')

fig.show()
2

Typical that having postwed a question an answer appears in another post from months ago

I just needed to add a color_discrete_mapp to my px.bar and it allows me to assign colors to my columns.

Working graphing code is as follows

fig = px.bar(df_merge[action_mask],
            color_discrete_map={
                '2019' : '#071633',
                '2020' : '#0DEFFF'
            }
            )

# Change the bar mode
fig.update_layout(barmode='group',
                  title='<b>Number of actions by unit<b>',
                  xaxis_categoryorder = 'category ascending',
                  height = 800,
                  plot_bgcolor='rgba(0,0,0,0)',
                  showlegend=True
                 )

fig.update_xaxes(tickangle=45,
                 title_text='<b>Unit<b>',
                 showline=True,
                 linewidth=1,
                 linecolor='#071633'
                )

fig.update_yaxes(title_text='<b>Count<b>',
                 showline=True,
                 linewidth=0.25,
                 linecolor='#071633')

fig.show()
``