Splom layout updating

đź“Š Plotly Python
1

I have some data which I am plotting using px.scatter_matrix giving me splom traces. However I think I am misunderstanding how I can update (or even if I can update) what I would think are “layout” attributes in a splom plot. Here is a MRP:

import plotly.express as px
df = px.data.gapminder().query("year==2007")
fig = px.scatter_matrix(df, dimensions=["pop", "lifeExp", "gdpPercap"],
                        color="continent", title="Gapminder 2007")
fig.show()
# Lets change the y label in the top left plot
fig = fig.update_yaxes(title_text="Population", row=1, col=1)
fig.show() # Nothing happens!

I read through the fundamentals of the figure carefully and when I print the figure I can see labels assigned to each trace, but I cannot figure out how these can be updated and why they are not a part of the layout. Would someone be able to help me understand what I am missing regarding the functinoality of splom plots and where I can go for a reference to understand the functionality going forward? Thank you so much for your help!

2

Hi @naveace welcome to the community and thanks for the MRP.

When I do not know how to alter specific items of a chart, I usually convert the figure into a dictionary with fig.to_dict() and inspect it. In general, plotly uses a nested structure like a dictionary or json.

So doing that with the px.scatter_matrix shows, that the label of the pop hides here:

fig.data[0]['dimensions'][0]['label']

You can change this to whatever you like via
fig.data[0]['dimensions'][0]['label']='Population'

Full code:

import plotly.express as px
df = px.data.gapminder().query("year==2007")
fig = px.scatter_matrix(df, dimensions=["pop", "lifeExp", "gdpPercap"],
                        color="continent", title="Gapminder 2007")

fig.data[0]['dimensions'][0]['label']='Population'
fig.show()

creates:
newplot (11)

There might be other ways to do this and maybe even built in functions, but my experience with these type of “special figures” is somewhat limited.

3

Thanks so much! Very helpful :slight_smile: