Set`categoryorder` to "category ascending/descending" for the alphanumerical order of the category names or "total ascending/descending" for numerical order of values.[categoryorder](https://plot.ly/python/reference/#layout-xaxis-categoryorder) for more information.

Set`categoryorder` to`"category ascending"` or`"category descending"` for the alphanumerical order of the category names or`"total ascending"` or`"total descending"` for numerical order of values.[categoryorder](https://plot.ly/python/reference/#layout-xaxis-categoryorder) for more information. Note that sorting the bars by a particular trace isn't possible right now - it's only possible to sort by the total values. Of course, you can always sort your data_before_ plotting it if you need more customization.

This example orders the bars alphabetically with`categoryorder: 'category ascending'`

import plotly.graph_objectsas go

x=['a','b','c','d']

fig= go.Figure(go.Bar(x=x,y=[2,5,1,9],name='Montreal'))

x=['b','a','c','d']

fig= go.Figure(go.Bar(x=x,y=[2,5,1,9],name='Montreal'))

fig.add_trace(go.Bar(x=x,y=[1,4,9,16],name='Ottawa'))

fig.add_trace(go.Bar(x=x,y=[6,8,4.5,8],name='Toronto'))

import plotly.graph_objectsas go

x=['a','b','c','d']

fig= go.Figure(go.Bar(x=x,y=[2,5,1,9],name='Montreal'))

fig= go.Figure(go.Bar(x=x,y=[2,5,1,9],name='Montreal'))

fig.add_trace(go.Bar(x=x,y=[1,4,9,16],name='Ottawa'))

fig.add_trace(go.Bar(x=x,y=[6,8,4.5,8],name='Toronto'))

fig.update_layout(barmode='stack',xaxis={'categoryorder':'array','categoryarray':['d','a','c','b']})

fig.show()

This example orders the bars by descending value with`categoryorder: 'total descending'`

import plotly.graph_objectsas go

x=['b','a','c','d']

fig= go.Figure(go.Bar(x=x,y=[2,5,1,9],name='Montreal'))

fig.add_trace(go.Bar(x=x,y=[1,4,9,16],name='Ottawa'))

fig.add_trace(go.Bar(x=x,y=[6,8,4.5,8],name='Toronto'))

fig.update_layout(barmode='stack',xaxis={'categoryorder':'total descending'})

fig.show()

See examples of horizontal bar charts[here](https://plot.ly/python/horizontal-bar-charts/).