Inconsistency in n_colors and 'rgb' color expression?

📊 Plotly Python
1

Hi,

I encountered a problem while using plotly.colors. I would be thankful if you explain me why this happened (or point me to any document).

The following code outputs a list of ‘rgb(three float numbers)’.

import plotly.colors as pc

pc.n_colors(pc.sequential.Viridis[0], pc.sequential.Viridis[1], 10, colortype='rgb')

For example, the first element of the list is ‘rgb(68.0, 1.0, 84.0)’, which is the same as pc.sequential.Viridis[0] if we ignore the decimal part. Nonetheless if I plot a polygon by

import plotly.graph_objects as go
import plotly.colors as pc

# Figure settings
xlim = [0, 16]
ylim = [0, 3]
clim = [0, 1]

if __name__ == '__main__':
    fig = go.Figure()

    fig.add_trace(
        go.Scatter(
            x=[0, 1, 1, 0],
            y=[0, 0, 1, 0],
            mode='none',
            fill='toself',
            fillcolor='rgb(68.0, 1.0, 84.0)'
        )
    )

    # Dummy trace to show a colorbar.
    dummy_trace = go.Scatter(
        x=xlim, y=ylim, mode='markers',
        marker=dict(
            size=0.1, color=clim, colorscale=pc.sequential.Viridis,
            colorbar=dict(thickness=10), showscale=True),
        hoverinfo='none'
    )

    fig.add_trace(dummy_trace)

    fig.update_layout(showlegend=False)

    fig.show()

the color of the polygon is different from ‘rgb(68, 1, 84)’. So, it seems that ‘rgb(68, 1, 84)’ and ‘rgb(68.0, 1.0, 84.0)’ are interpreted differently, but plotly.colors.n_colors is ignorant of this.

Am I missing something or using n_colors wrongly?

Thank you in advance!

Best regards,
Tadashi