How to build columns in Plotly with multiple values sorted by value? - pandas

Question

I have a dataframe with data, the code is below, in which there are 3 columns - date, system and number, building a bar graph in Plotly I get two bars in which I cannot set the sorting by values, they are atomatically sorted by name.
import pandas as pd
import numpy as np
data = [('2022-10-01','Pay1',644), ('2022-10-01','Pay2',1460), ('2022-10-01','Pay3',1221), ('2022-10-01','Pay4',1623),\
('2022-10-01','Pay5',1904), ('2022-10-01','Pay6',1853), ('2022-10-01','Pay7',1826), ('2022-10-01','Pay8',247),\
('2022-10-01','Pay9',713), ('2022-10-01','Pay10',1159), ('2022-10-02','Pay1',755), ('2022-10-02','Pay2',786),\
('2022-10-02','Pay3',623), ('2022-10-02','Pay4',1766), ('2022-10-02','Pay5',1141), ('2022-10-02','Pay6',362),\
('2022-10-02','Pay7',1097), ('2022-10-02','Pay8',655), ('2022-10-02','Pay9',1569), ('2022-10-02','Pay10',796)]
data = pd.DataFrame(data,columns=['date','system','number'])
import plotly.express as px
fig = px.bar(data, x='date', y='number',
color='system')
fig.show()
I want to get a bar that will be sorted by value, from smallest to largest in each case

Answer 1

The expected graph is a stacked graph using the same color for categorical variables, and the order of the graphs is in order of increasing numerical value. To make the categorical variables the same color, create a dictionary of default discrete to maps and system columns. Add a column of colors to each data frame. Extract data frames by date, sort them in numerical order of size, and loop through them row by row.
import plotly.graph_objects as go
import plotly.express as px
colors = px.colors.qualitative.Plotly
system_name = data['system'].unique()
colors_dict = {k:v for k,v in zip(system_name, colors)}
# print(colors_dict)
fig = go.Figure()
dff = data.query('date =="2022-10-01"')
dff = dff.sort_values('number',ascending=False)
dff['color'] = dff['system'].map(colors_dict)
for row in dff.itertuples():
fig.add_trace(go.Bar(x=[row.date], y=[row.number], name=row.system, marker_color=row.color))
fig.update_layout(barmode='stack')
dfm = data.query('date =="2022-10-02"')
dfm = dfm.sort_values('number',ascending=False)
dfm['color'] = dfm['system'].map(colors_dict)
for row in dfm.itertuples():
fig.add_trace(go.Bar(x=[row.date], y=[row.number], name=row.system, marker_color=row.color))
fig.update_layout(barmode='stack')
names = set()
fig.for_each_trace(
lambda trace:
trace.update(showlegend=False)
if (trace.name in names) else names.add(trace.name))
fig.show()