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pythoncolorsplotlyplotly-python

Plotly - color cycle setting from a colormap

For matplotlib, I used this code to change a default color cycle setting, so that I could plot multiple lines with colors in this cycle.


n = 24
color = plt.cm.viridis(np.linspace(0, 1,n))
mpl.rcParams['axes.prop_cycle'] = cycler.cycler('color', color) 

for i in range(30):
    plt.plot(x,y,data[data["col1"]==i]) 
plt.show()

How can I do this for plotly as well?

fig = px.line(data[data["col1"]==i],x,y)

for i in range(30):
    fig.add_scatter(x,y,data[data["col1"]==i],mode="line")
Solution

  • I often use from itertools import cycle and next(<list of colors>) where <list of colors> could be any sequence of colors, like px.colors.qualitative.Alphabet.

    Here's a setup that comes close to what you're looking for:

    fig = go.Figure()
for i in range(lines):
    color =  next(col_cycle)
    fig.add_scatter(x = np.arange(0,rows),
                    y = np.random.randint(-5, 6, size=rows).cumsum(),
                    mode="lines",
                    line_color = color,
                    name = color
                   )

    Plot

    enter image description here

    Complete code:

    from itertools import cycle
import numpy as np
col_cycle = cycle(px.colors.qualitative.Alphabet)

rows = 10
lines = 30

fig = go.Figure()
for i in range(lines):
    color =  next(col_cycle)
    fig.add_scatter(x = np.arange(0,rows),
                    y = np.random.randint(-5, 6, size=rows).cumsum(),
                    mode="lines",
                    line_color = color,
                    name = color
                   ) 
fig.show()