update specific subplot axes in plotly

Question

Setup:

• I'm tring to plot a subplots with plotly library, but can't figure out how to reference a specific subplots' axis to change its' name (or other properties).
• In Code 1 I show a simple example where I add two plots one on thop of the other with plotly.subplots.make_subplots.

Code 1

import numpy as np
from plotly.subplots import make_subplots
from math import exp

fig = make_subplots(2, 1)

x = np.linspace(0, 10, 1000)
y = np.array(list(map(lambda x: 1 / (1 + exp(-0.1 * x + 5)), x)))
fig.add_trace(
    go.Scatter(
        x=x,
        y=y,
        name=f'\N{Greek Small Letter Sigma}(x)',
        showlegend=True
    ),
    row=1,
    col=1
)

x = np.where(np.random.randint(0, 2, 100)==1)[0]
fig.add_trace(
    go.Scatter(
        x=x,
        y=np.zeros_like(x),
        name=f'Plot 2',
        mode='markers', 
        marker=dict(
                symbol='circle-open',
                color='green',
                size=5
            ),
        showlegend=True
    ),
    row=2,
    col=1
)
fig.show()

What I've Tried

I've tried using the fig.update_xaxes() after each trace addition, but it messes the plots and does not produce the desired output, as shown in Code 2.

Code 2:

import numpy as np
from plotly.subplots import make_subplots
from math import exp

fig = make_subplots(2, 1)

x = np.linspace(0, 10, 1000)
y = np.array(list(map(lambda x: 1 / (1 + exp(-0.1 * x + 5)), x)))
fig.add_trace(
    go.Scatter(
        x=x,
        y=y,
        name=f'\N{Greek Small Letter Sigma}(x)',
        showlegend=True
    ),
    row=1,
    col=1
)
fig.update_xaxes(title_text='x')
x = np.where(np.random.randint(0, 2, 100)==1)[0]
fig.add_trace(
    go.Scatter(
        x=x,
        y=np.zeros_like(x),
        name=f'Plot 2',
        mode='markers', 
        marker=dict(
                symbol='circle-open',
                color='green',
                size=5
            ),
        showlegend=True
    ),
    row=2,
    col=1
)
fig.update_xaxes(title_text='active users')
fig.show()

which results in (note the active users being printed on the top):

My Questions:

1. How can I assign the top plot x axis the label x, and active users label to the x axis of the bottom plot?
2. And in general - how can I access the properties of an individual subplot?

Answer 1

With the help from this answer I as able to solve it, by referencing the xaxis for plot on the position row=1, col=1 and the xaxis1 for the plot on the row=2, col=1 position. The full solution is in Code 1.

Code 1:

import numpy as np
from plotly.subplots import make_subplots
from math import exp

fig = make_subplots(2, 1)

x = np.linspace(0, 10, 1000)
y = np.array(list(map(lambda x: 1 / (1 + exp(-0.1 * x + 5)), x)))
fig.add_trace(
    go.Scatter(
        x=x,
        y=y,
        name=f'\N{Greek Small Letter Sigma}(x)',
        showlegend=True
    ),
    row=1,
    col=1
)
fig['layout']['xaxis'].update(title_text='x')

x = np.where(np.random.randint(0, 2, 100)==1)[0]
fig.add_trace(
    go.Scatter(
        x=x,
        y=np.zeros_like(x),
        name=f'Plot 2',
        mode='markers', 
        marker=dict(
                symbol='circle-open',
                color='green',
                size=5
            ),
        showlegend=True
    ),
    row=2,
    col=1
)
fig['layout']['xaxis2'].update(title_text='active users')

fig.show()

Cheers.