问题：在matplotlib中设置y轴限制
我需要在matplotlib上设置y轴限制的帮助。这是我尝试失败的代码。
import matplotlib.pyplot as plt
plt.figure(1, figsize = (8.5,11))
plt.suptitle('plot title')
ax = []
aPlot = plt.subplot(321, axisbg = 'w', title = "Year 1")
ax.append(aPlot)
plt.plot(paramValues,plotDataPrice[0], color = '#340B8C',
marker = 'o', ms = 5, mfc = '#EB1717')
plt.xticks(paramValues)
plt.ylabel('Average Price')
plt.xlabel('Mark-up')
plt.grid(True)
plt.ylim((25,250))
使用此图的数据，我得到的Y轴限制为20和200。但是，我希望限制为20和250。
I need help with setting the limits of y-axis on matplotlib. Here is the code that I tried, unsuccessfully.
import matplotlib.pyplot as plt
plt.figure(1, figsize = (8.5,11))
plt.suptitle('plot title')
ax = []
aPlot = plt.subplot(321, axisbg = 'w', title = "Year 1")
ax.append(aPlot)
plt.plot(paramValues,plotDataPrice[0], color = '#340B8C',
marker = 'o', ms = 5, mfc = '#EB1717')
plt.xticks(paramValues)
plt.ylabel('Average Price')
plt.xlabel('Mark-up')
plt.grid(True)
plt.ylim((25,250))
With the data I have for this plot, I get y-axis limits of 20 and 200. However, I want the limits 20 and 250.
回答 0
尝试这个 。也适用于子图。
axes = plt.gca()
axes.set_xlim([xmin,xmax])
axes.set_ylim([ymin,ymax])
Try this . Works for subplots too .
axes = plt.gca()
axes.set_xlim([xmin,xmax])
axes.set_ylim([ymin,ymax])
回答 1
您的代码也对我有用。但是，另一种解决方法是获取图的轴，然后仅更改y值：
x1,x2,y1,y2 = plt.axis()
plt.axis((x1,x2,25,250))
Your code works also for me. However, another workaround can be to get the plot’s axis and then change only the y-values:
x1,x2,y1,y2 = plt.axis()
plt.axis((x1,x2,25,250))
回答 2
您可以做的一件事是使用matplotlib.pyplot.axis自行设置轴范围。
matplotlib.pyplot.axis
from matplotlib import pyplot as plt
plt.axis([0, 10, 0, 20])
0,10用于x轴范围。0,20是y轴范围。
或者您也可以使用matplotlib.pyplot.xlim或matplotlib.pyplot.ylim
matplotlib.pyplot.ylim
plt.ylim(-2, 2)
plt.xlim(0,10)
One thing you can do is to set your axis range by yourself by using matplotlib.pyplot.axis.
matplotlib.pyplot.axis
from matplotlib import pyplot as plt
plt.axis([0, 10, 0, 20])
0,10 is for x axis range.
0,20 is for y axis range.
or you can also use matplotlib.pyplot.xlim or matplotlib.pyplot.ylim
matplotlib.pyplot.ylim
plt.ylim(-2, 2)
plt.xlim(0,10)
回答 3
您可以从中实例化对象matplotlib.pyplot.axes并对其进行调用set_ylim()。就像这样：
import matplotlib.pyplot as plt
axes = plt.axes()
axes.set_ylim([0, 1])
You can instantiate an object from matplotlib.pyplot.axes and call the set_ylim() on it. It would be something like this:
import matplotlib.pyplot as plt
axes = plt.axes()
axes.set_ylim([0, 1])
回答 4
这至少在matplotlib 2.2.2版中有效：
plt.axis([None, None, 0, 100])
大概这是设置例如xmin和ymax等的好方法。
This worked at least in matplotlib version 2.2.2:
plt.axis([None, None, 0, 100])
Probably this is a nice way to set up for example xmin and ymax only, etc.
回答 5
要添加到@Hima的答案中，如果要修改当前的x或y限制，可以使用以下内容。
import numpy as np # you probably alredy do this so no extra overhead
fig, axes = plt.subplot()
axes.plot(data[:,0], data[:,1])
xlim = axes.get_xlim()
# example of how to zoomout by a factor of 0.1
factor = 0.1
new_xlim = (xlim[0] + xlim[1])/2 + np.array((-0.5, 0.5)) * (xlim[1] - xlim[0]) * (1 + factor)
axes.set_xlim(new_xlim)
当我想从默认绘图设置中缩小或放大一点时，我发现这特别有用。
To add to @Hima’s answer, if you want to modify a current x or y limit you could use the following.
import numpy as np # you probably alredy do this so no extra overhead
fig, axes = plt.subplot()
axes.plot(data[:,0], data[:,1])
xlim = axes.get_xlim()
# example of how to zoomout by a factor of 0.1
factor = 0.1
new_xlim = (xlim[0] + xlim[1])/2 + np.array((-0.5, 0.5)) * (xlim[1] - xlim[0]) * (1 + factor)
axes.set_xlim(new_xlim)
I find this particularly useful when I want to zoom out or zoom in just a little from the default plot settings.
回答 6
这应该工作。您的代码对我有效，例如Tamás和Manoj Govindan。看来您可以尝试更新Matplotlib。如果您无法更新Matplotlib（例如，如果您的管理权限不足），也许使用其他后端matplotlib.use()可能会有所帮助。
This should work. Your code works for me, like for Tamás and Manoj Govindan. It looks like you could try to update Matplotlib. If you can’t update Matplotlib (for instance if you have insufficient administrative rights), maybe using a different backend with matplotlib.use() could help.
回答 7
仅用于微调。如果只想设置轴的一个边界，而另一个边界不变，则可以选择以下一个或多个语句
plt.xlim(right=xmax) #xmax is your value
plt.xlim(left=xmin) #xmin is your value
plt.ylim(top=ymax) #ymax is your value
plt.ylim(bottom=ymin) #ymin is your value
查看有关xlim和ylim的文档
Just for fine tuning. If you want to set only one of the boundaries of the axis and let the other boundary unchanged, you can choose one or more of the following statements
plt.xlim(right=xmax) #xmax is your value
plt.xlim(left=xmin) #xmin is your value
plt.ylim(top=ymax) #ymax is your value
plt.ylim(bottom=ymin) #ymin is your value
Take a look at the documentation for xlim and for ylim
回答 8
如果某个轴（由问题下方代码下方的代码生成）与第一个轴共享范围，请确保将范围设置为该轴的最后一个绘图之后。
If an axes (generated by code below the code shown in the question) is sharing the range with the first axes, make sure that you set the range after the last plot of that axes.
