pythonmatplotlibseabornkdeplot

How can I disable the gradient color with kdeplot?

When I run the below code, I get a figure with gradient color (from black to orange). Please look at the attached figure. Whereas I want to get a figure only with single color, orange (not figure with a gradient color). How can I do that?

My code:

#!/usr/bin/python3
import numpy as np
import pylab as plot
import matplotlib.pyplot as plt
import numpy, scipy, pylab, random
from matplotlib.ticker import MultipleLocator
import matplotlib as mpl
from matplotlib.ticker import MaxNLocator
import seaborn as sns
import pandas as pd

fig, ax = plt.subplots(figsize=(4, 2))

df = pd.read_csv('input.txt', sep="\s\s+", engine='python')
sns.kdeplot(data=df, label = "s1", color = "orange", cmap=None)
plt.xlabel('x', fontsize=7)
plt.ylabel('y', fontsize=7)

for axis in ['top','bottom','left','right']:
  ax.spines[axis].set_linewidth(0.5)

plt.savefig("plot.png", dpi=300, bbox_inches='tight')

input.txt:

   0.43082    0.45386
   0.35440    0.91632
   0.16962    0.85031
   0.07069    0.54742
   0.31648    1.06689
   0.57874    1.17532
   0.18982    1.01678
   0.31012    0.54656
   0.31133    0.81658
   0.53612    0.50940
   0.36633    0.83130
   0.37021    0.74655
   0.28335    1.30949
   0.11517    0.63141
   0.24908    1.04403
  -0.28633    0.46673
  -0.13251    0.33448
  -0.00568    0.53939
  -0.03536    0.76191
   0.24695    0.92592

The output figure that I get is here: plot.png

Solution

  • Using Seaborn v0.11.2.

    Solution:

    The expected output is obtained if you specify x and y arguments of seaborn.kdeplot as the column names of the DataFrame (after appropriately reading the data as suggested in Timeless's answer, i.e., by specifying header=None in pd.read_csv):

    x, y: vectors or keys in data
    Variables that specify positions on the x and y axes.

    df = pd.read_csv('input.txt', sep="\s\s+", engine='python', header=None)
print(df)
sns.kdeplot(data=df, x=0, y=1, color = "orange")

    df:

              0        1
0   0.43082  0.45386
1   0.35440  0.91632
2   0.16962  0.85031
3   0.07069  0.54742
4   0.31648  1.06689
5   0.57874  1.17532
6   0.18982  1.01678
7   0.31012  0.54656
8   0.31133  0.81658
9   0.53612  0.50940
10  0.36633  0.83130
11  0.37021  0.74655
12  0.28335  1.30949
13  0.11517  0.63141
14  0.24908  1.04403
15 -0.28633  0.46673
16 -0.13251  0.33448
17 -0.00568  0.53939
18 -0.03536  0.76191
19  0.24695  0.92592

    Expected figure output:

    enter image description here

    sns.kdeplot plots distribution of each column in the data when data is passed to it without specifying x and y:

    The code in the question throws an error:

    AttributeError: 'Line2D' object has no property 'cmap'

    If you now don't pass cmap to sns.kdeplot and use:

    df = pd.read_csv('input.txt', sep="\s\s+", engine='python',)
sns.kdeplot(data=df, label = "s1", color="orange")

    it returns (notice the legend labels of the line plots):

    enter image description here