Python Matplotlib散点图添加x轴标签

Question

I have this following code in order to generate scatterplots

            import matplotlib.pyplot as plt

              line = plt.figure()    
              plt.plot(xvalue, yvalue)
              plt.grid(True)
              plt.savefig("test.png")
              plt.show()

and here is the screenshot of the plot:

I am just wondering if i could change the x-axis labels into strings. I have stored all the labels in

    xlabel = ['2015/4/1', '2015/4/11', '2015/4/12', '2015/4/18', '2015/4/19'...]

Is there any function for matplotlib so that i could set x-axis labels to the values in "xlabel"?

many thx!

ALso my labels are overlapped, anything i could do to fix this problem? thx!

Answer 1

Here is my answer. You target was to plot the datetime as xticklabel.
I always do something like this. Code like this:

## For example, I have 9 daily value during 2013-04-01 to 2014-04-10
start = datetime.datetime.strptime("01-04-2013", "%d-%m-%Y")
end = datetime.datetime.strptime("10-04-2013", "%d-%m-%Y")
date = [start + datetime.timedelta(days=x) for x in range(0, (end-start).days)]

plt.figure(figsize=(12,4))
## y is the data I want to plot
ind = np.arange(len(y))
ax=plt.subplot()
plt.plot(ind,y,lw = 3)
k = []
for i in range(0,len(ind),1):
    k.append(str(date[i])[0:10])

plt.xticks(ind,k,rotation=65)

Update

To solve the overlap problem, I recommend the code below:

for label in ax.xaxis.get_ticklabels()[::2]:
    label.set_visible(False)       

For daily value in a month, you can get a figure like this:

Answer 2

Do:

plt.xticks(xs, labels)

Where xs is a list of the positions for the ticks, and labels is the list of labels.