python - Mix of line and scatter plots from pandas dataframe in a single plot using the tick frequency of the first plot only

Question

I am wanting to compare data within a dataframe, plotting some of the data as lines, and other columns as scatter. My actual data is a combination of model output and observations, I want the observations to be scatter, and the model to be lines.

The observations have a LOT of Nan values (most times steps do not have an observation).

This MWE duplicates the issue I'm having

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt

base = datetime.datetime.today()
date_list = [base - datetime.timedelta(days=x) for x in range(40)]

df = pd.DataFrame(data = {
    "Time": date_list,
    "Chocolate": np.random.rand(40), 
    "Strawberry": np.random.rand(40), 
    "Fake Chocolate": np.random.rand(40), 
    "Fake Strawberry": np.random.rand(40), 
})
df.iloc[3,3] = np.nan

ax1 = df.plot(x = 'Time', y = ["Chocolate","Strawberry"])

ax1 = df.plot(x = 'Time', y = ["Chocolate","Strawberry"])
ax2 = df.plot.scatter(x = 'Time', y = ['Fake Chocolate'], marker = '^', ax = ax1)
ax3 = df.plot.scatter(x = 'Time', y = ['Fake Strawberry'], marker = '*', ax = ax1, color = '#ff7f0e')

I want to have the x-axis like in the first plot, so taking the style of the line plot where you don't have EVERY date trying to print in a tiny space. How do I do this?

I am using ax1.set to set the x and y-axis labels.

and if I can sneak in a second question, why is it possible to do multiple lines using y = [] but not possible for the scatter plots?

标签： pythonpandasmatplotlibplot

Answer 1

Just add plt.xticks(rotation=45) to the end of your script and you will be fine.

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
import datetime

base = datetime.datetime.today()
date_list = [base - datetime.timedelta(days=x) for x in range(40)]

df = pd.DataFrame(data = {
    "Time": date_list,
    "Chocolate": np.random.rand(40), 
    "Strawberry": np.random.rand(40), 
    "Fake Chocolate": np.random.rand(40), 
    "Fake Strawberry": np.random.rand(40), 
})
df.iloc[3,3] = np.nan

ax1 = df.plot(x = 'Time', y = ["Chocolate","Strawberry"])

ax1 = df.plot(x = 'Time', y = ["Chocolate","Strawberry"])
ax2 = df.plot.scatter(x = 'Time', y = ['Fake Chocolate'], marker = '^', ax = ax1)
ax3 = df.plot.scatter(x = 'Time', y = ['Fake Strawberry'], marker = '*', ax = ax1, color = '#ff7f0e')
plt.xticks(rotation=45);