Question

I have about 15 series which I wish to scatter plot against a series of values of X.

However, for some values in my series I don’t want anything to be plotted. Is there a value I can use as a dummy, so that series lengths are the same, but matplotlib won’t plot that point?

For example if I have [1,2,3,4,5,6,7,8,9] as my x axis, and I have a series on the Y axis ['a', 'b', 'c', 'd', 'e', foo, 'g','h','i'] and I don’t want to plot foo against 6, I’d like to replace foo with some value that won’t be plotted.

I should point out that my x and y values are datetimes. I wasn’t expecting that to be necessary info, but it seems that whilst a NaN works for plotting floats, it doesn’t work for datetimes.

Answer 1

So to solve this, I used Nones as dummy values, and created

def find_indices(haystack, needle):
  return [i for i,x in enumerate(haystack) if needle == x]

def remove_at(xs, indices):
  return [x for i,x in enumerate(xs) if i not in indices]

And then

nones_at = find_indices(y_values, None)
x_values = remove_at(x_axis, nones_at)
y_values = remove_at(y_values, nones_at)
pyplot.plot(x_values, y_values)