If the length of the c argument to matplotlib.pyplot.scatter doesn't match the size of the x and y arguments, a confusing error message is raised: Invalid RGBA argument. Contrast this with the error that results if x and y are not the same size: x and y must be the same size. The error message for an incorrect size c array should be made more clear.
Code for reproduction
import numpy, matplotlib.pyplot as plt
xs, ys = numpy.random.random((2, 10))
c = numpy.random.random(9)
plt.scatter(xs, ys, c=c)
Actual outcome
/usr/local/lib/python3.6/site-packages/matplotlib/colors.py in _to_rgba_no_colorcycle(c, alpha)
192 # float)` and `np.array(...).astype(float)` all convert "0.5" to 0.5.
193 # Test dimensionality to reject single floats.
--> 194 raise ValueError("Invalid RGBA argument: {!r}".format(orig_c))
195 # Return a tuple to prevent the cached value from being modified.
196 c = tuple(c.astype(float))
ValueError: Invalid RGBA argument: 0.58430716187559439
Expected outcome
ValueError: c and x must be the same size
- Matplotlib Version: 2.0.2
- Python Version: 3.6.1
If the length of the
cargument tomatplotlib.pyplot.scatterdoesn't match the size of thexandyarguments, a confusing error message is raised:Invalid RGBA argument. Contrast this with the error that results ifxandyare not the same size:x and y must be the same size. The error message for an incorrect sizecarray should be made more clear.Code for reproduction
Actual outcome
Expected outcome