Using Facet_col with Plotly Express Scatter_Polar charts

Question

Is it possible to use the facet_col or facet_row option when using px.scatter_polar? I have tried, but get “TypeError: scatter_polar() got an unexpected keyword argument ‘facet_col’”.

import plotly.express as px
import pandas as pd

df=pd.DataFrame({'WD': {0: 'N', 1: 'N', 2: 'N', 3: 'N', 4: 'N', 5: 'N', 6: 'NNE', 7: 'NNE', 8: 'NNE', 9: 'NNE', 10: 'NNE', 11: 'NNE'}, 'WS': {0: 1, 1: 2, 2: 3, 3: 4, 4: 5, 5: 6, 6: 1, 7: 2, 8: 3, 9: 4, 10: 5, 11: 6}, 'Lines': {0: 0, 1: 3, 2: 5, 3: 12, 4: 1, 5: 0, 6: 0, 7: 1, 8: 4, 9: 5, 10: 2, 11: 0}, 'Site': {0: 'EQ21301', 1: 'EQ21309', 2: 'EQ21301', 3: 'EQ21306', 4: 'EQ21301', 5: 'EQ21301', 6: 'EQ21301', 7: 'EQ21301', 8: 'EQ21306', 9: 'EQ21306', 10: 'EQ21306', 11: 'EQ21309'}})
fig = px.scatter_polar(df, r="WS", theta="WD",size='Lines',facet_col='Site',
                       color='WS',color_discrete_sequence=px.colors.sequential.YlOrRd,template='plotly_dark') 


fig.show()

I know I can create it with make_subplots, but thought this method might be nicer and means I don't have to add extra code every time the number of Sites increases.

@WilH Anyone interested in answering your question would have to copy your and store it in a folder corresponding to your designated filname in order to reproduce your scenario. There are ways you can make it easier for everybody and at the same time increase your chances of getting a useful answer faster. [Here is one way](https://stackoverflow.com/questions/63163251/pandas-how-to-easily-share-a-sample-dataframe-using-df-to-dict/63163254#63163254) — vestland, May 31 '21 at 13:11
It seems as if `facet_col` is not in the list of accepted arguments for ScatterPolar Charts as seen here https://www.geeksforgeeks.org/plotly-express-scatter_polar-function-in-python/. It seems as if the only option here is to use `make_subplots` — AS11, May 31 '21 at 15:40

score 1 · Accepted Answer · answered Jun 01 '21 at 09:31

simply it's not a capability...
use plotly express to generate a figure as base for getting parameters
make_subplots() for each Site
copy across wanted parameters from trace
copy across wanted parameters from layout

import plotly.express as px
import plotly.graph_objects as go
import pandas as pd
from plotly.subplots import make_subplots

df=pd.DataFrame({'WD': {0: 'N', 1: 'N', 2: 'N', 3: 'N', 4: 'N', 5: 'N', 6: 'NNE', 7: 'NNE', 8: 'NNE', 9: 'NNE', 10: 'NNE', 11: 'NNE'}, 'WS': {0: 1, 1: 2, 2: 3, 3: 4, 4: 5, 5: 6, 6: 1, 7: 2, 8: 3, 9: 4, 10: 5, 11: 6}, 'Lines': {0: 0, 1: 3, 2: 5, 3: 12, 4: 1, 5: 0, 6: 0, 7: 1, 8: 4, 9: 5, 10: 2, 11: 0}, 'Site': {0: 'EQ21301', 1: 'EQ21309', 2: 'EQ21301', 3: 'EQ21306', 4: 'EQ21301', 5: 'EQ21301', 6: 'EQ21301', 7: 'EQ21301', 8: 'EQ21306', 9: 'EQ21306', 10: 'EQ21306', 11: 'EQ21309'}})
# create px figure to copy formatting from
fig = px.scatter_polar(df, r="WS", theta="WD",size='Lines',
                       color='WS',color_discrete_sequence=px.colors.sequential.YlOrRd,template='plotly_dark') 


# make sub-plots for all "Site"
spfig = make_subplots(
    cols=len(df["Site"].unique()),
    specs=[[{"type": "polar"} for s in df["Site"].unique()]],
    subplot_titles=df["Site"].unique()
)
# use base go capability and copy wanted parameters from px trace
for c, site in enumerate(df["Site"].unique()):
    dft = df.loc[df["Site"].eq(site)]
    spfig.add_trace(
        go.Scatterpolar(
            {
                **fig.to_dict()["data"][0],
                **{
                    "r": dft["WS"],
                    "theta": dft["WD"],
                    "name": site,
                    "marker": {
                        **fig.to_dict()["data"][0]["marker"],
                        **{"size": dft["Lines"], "color": dft["WS"]},
                    },
                },
            },
        ),
        row=1,
        col=c + 1,
    )

# finally copy across layout parameters
spfig = spfig.update_layout({ **fig.to_dict()["layout"], **spfig.to_dict()["layout"]})
spfig.layout.template = fig.layout.template
for axis in ["polar","polar2","polar3"]:
    spfig.layout[axis]["angularaxis"] = fig.layout.polar["angularaxis"]
    
# and we're done...
spfig

Using Facet_col with Plotly Express Scatter_Polar charts

1 Answers1