Plotly: Update all yaxes fonts and give individual scale using preset layout

Question

I have a dataset df = ['Group', 'subgroup', 'x', 'y'], for which I would like to

• plot scatter x vs y- (Done)
• color = subgroup (Done)
• facet_rows = Group (Done)

Now I would like to update the plot with my own layout (my_layout); however I am runing into 2 problems:

1. When i pass fig.update_layout(my_layout), it is only updating one yaxis, instead of all.
2. using "matches": None, for yaxis, isn't resulting in 2 separate scales for the yaxis.

Using fig.update_yaxes(matches=None)2, updates the yaxis correctly, however I would like to have it all in my_layout, so that each time i generate a new plot I can update all the layout with one comand.

Here is the code:

#my layoyt, shoudl update all plots yaxis, and set indivuual scales for yaxis
my_layout = go.Layout({
                       "yaxis": {"matches": None, "titlefont": dict(family = 'Times new Roman',size = 30, color = 'black'), "tickfont": dict(family = 'Times new Roman',size = 30, color = 'black'),},
                       "xaxis": {"titlefont": dict(family = 'Times new Roman',size = 30, color = 'black'), "tickfont": dict(family = 'Times new Roman',size = 30, color = 'black'),},
                                     
                       })


 #the df
df =pd.DataFrame({
    "Group" : [1,1,1,1,2,2,2,2],
    "subgroup": ["A","B","C","D","E","F","G","H"],
    "x" : [1,2,3,4,1,2,3,4],
    "y" : [2,4,6,8,20,40,60,80]
    
    
})

fig = px.scatter(df, x = "x", y= "y", color="subgroup", facet_row="Group",   template = "simple_white")
fig.update_layout(my_layout)
 #with this line commented in plots yaxis update correctly, hower I am hoping to put all layout components into one object i can call.   
# fig.update_yaxes(matches=None)
fig.show()

Answer 1

The subplot settings in plotly are assigned in order: xaxis,xaxis2,xaxis3, and so on. y-axis is the same. Therefore, you need to add yaxis2 to your own layout. fig.layout allows you to visualize the structure of the graph in a dictionary format.

import plotly.graph_objects as go
import plotly.express as px
import pandas as pd

 #the df
df =pd.DataFrame({
    "Group" : [1,1,1,1,2,2,2,2],
    "subgroup": ["A","B","C","D","E","F","G","H"],
    "x" : [1,2,3,4,1,2,3,4],
    "y" : [2,4,6,8,20,40,60,80]
})

fig = px.scatter(df, x="x", y="y", color="subgroup", facet_row="Group", template="simple_white")

#my layoyt, shoudl update all plots yaxis, and set indivuual scales for yaxis
my_layout = go.Layout({"yaxis": {"matches": None,
                                 "titlefont": dict(family='Times new Roman',size=30, color='black'),
                                 "tickfont": dict(family='Times new Roman',size=30, color='black'),},
                       "yaxis2": {"matches": None,
                                 "titlefont": dict(family='Times new Roman',size=30, color='black'),
                                 "tickfont": dict(family='Times new Roman',size=30, color='black'),},
                       "xaxis": {"titlefont": dict(family='Times new Roman',size=30, color='black'),
                                 "tickfont": dict(family='Times new Roman',size=30, color='black'),},
                      })

fig.update_layout(my_layout)
fig.show()

Edit: To optimize the y-axis range, I can't do it in express, so the only way is to subplot it in graph_objects. I'm reusing the data created in express and subplotting it. We decided that two different ways to handle this would be more beneficial to plotly users.

fig = make_subplots(rows=2, cols=1, shared_xaxes=True)
fig_data = px.scatter(df, x="x", y="y", color="subgroup", facet_row="Group", template="simple_white")

for i in range(8):
    if i <=3:
        fig.add_trace(fig_data.data[i])
    else:
        fig.add_trace(fig_data.data[i])
        
#my layoyt, shoudl update all plots yaxis, and set indivuual scales for yaxis
my_layout = go.Layout({"yaxis": {"matches": None,
                                 "titlefont": dict(family='Times new Roman',size=30, color='black'),
                                 "tickfont": dict(family='Times new Roman',size=30, color='black'),},
                       "yaxis2": {"matches": None,
                                 "titlefont": dict(family='Times new Roman',size=30, color='black'),
                                 "tickfont": dict(family='Times new Roman',size=30, color='black'),},
                       "xaxis2": {"titlefont": dict(family='Times new Roman',size=30, color='black'),
                                 "tickfont": dict(family='Times new Roman',size=30, color='black'),},
                       "template":'simple_white',
                      })

fig.update_layout( my_layout)
fig.layout.legend.tracegroupgap = 1
fig.show()