PyPlot: color scatter plot data based on target value

Question

I have a data frame with 2 dimensions. i.e.

data = [[  7.08535569   5.20423916]
 [ -6.12292297  -9.79831639]
 [ -0.14405156   0.02112219]
 ...
 [ -2.93838878   2.4744518 ]
 [  8.07134259 -10.8165695 ]
 [  5.14161567   2.68737039]]

I also have a target value for each index i.e.

target = [-1, 1, 1, -1 ... -1, 1, -1, -1]

What is the easiest way to use PyPlot to color code the points based on their target value?

Currently I have

X = data[:,0]
y = data[:,1]

plt.plot(X, y, 'ro')
plt.show()

pygeek · Accepted Answer · 2020-09-18T19:08:59.117

1

Use scatter, which accepts additional arguments for color map:

...

data = [[  7.08535569   5.20423916]
 [ -6.12292297  -9.79831639]
 [ -0.14405156   0.02112219]
 ...
 [ -2.93838878   2.4744518 ]
 [  8.07134259 -10.8165695 ]
 [  5.14161567   2.68737039]]

...

plt.scatter(x, y, c=target, s=500, cmap='gray')
plt.show()

...

References:

Matplotlib scatterplot; colour as a function of a third variable

edited Sep 18 '20 at 19:08

answered Sep 18 '20 at 18:39

pygeek

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The data I have is a scatter plot, not a line graph like the SO post you linked. Im very new at mpl, are these treated the same? – SwimMaster Sep 18 '20 at 19:02
@SwimMaster I've updated my answer for scatter plot – pygeek Sep 18 '20 at 19:04

PyPlot: color scatter plot data based on target value

1 Answers1