来自 seaborn distplot 的 matplotlib vlines 动态 ymax 参数

Question

I'm plotting a seaborn distplot from pandas dataframe as my initial working matplotlib canvas. Then to add more info to the canvas I'm using vlines as vertical markers. However I didn't find a trivial way to define dynamic ymax param for vlines, since it is distribution dependent.

sns.distplot(data.values) # distribution chart
plt.vlines(x=[1,2], ymin=0, ymax=?)

Is there a way to pass the ymax acccording to the highest value in the chart? (so the plot height and the vertical lines height will be aligned). I considered something like:

plt.vlines(x=[1,2], ymin=0, ymax=data.values.max())

However the maximal value of data.values is actually represented on the X axis.

Answer 1

You may loop over the input points (useful if there aren't too many, say <=10)

for i in [1,2]:
    ax.axvline(i)

Or you can supply a blended transform for the vlines ,

ax.vlines(x=[1,2], ymin=0, ymax=1, transform=ax.get_yaxis_transform())

Answer 2

I found a way to retrieve the coordinates of the canvas:

dist = sns.distplot(data.values)
ymin,ymax = dist.get_ylim()

Then it's quite straightforward:

plt.vlines(x=[1,2], ymin=ymin, ymax=ymax)