這個matlab代碼相應的matplotlib代碼是什麼

Question

我想離開matlab並改用python + matplotlib。但是，我還沒有真正弄清matlab'handles'的matplotlib等價物是什麼。所以這裏有一些matlab代碼，我返回句柄，以便我可以改變某些屬性。這段代碼使用matplotlib的確切等價物是什麼？我經常在matlab中使用句柄的'Tag'屬性，並使用'findobj'。這可以用matplotlib來完成嗎？

% create figure and return figure handle 
h = figure(); 
% add a plot and tag it so we can find the handle later 
plot(1:10, 1:10, 'Tag', 'dummy') 
% add a legend 
my_legend = legend('a line') 
% change figure name 
set(h, 'name', 'myfigure') 
% find current axes 
my_axis = gca(); 
% change xlimits 
set(my_axis, 'XLim', [0 5]) 
% find the plot object generated above and modify YData 
set(findobj('Tag', 'dummy'), 'YData', repmat(10, 1, 10)) 

Answer 1

有一個findobj方法matplotlib太：

import matplotlib.pyplot as plt 
import numpy as np 

h = plt.figure() 
plt.plot(range(1,11), range(1,11), gid='dummy') 
my_legend = plt.legend(['a line']) 
plt.title('myfigure') # not sure if this is the same as set(h, 'name', 'myfigure') 
my_axis = plt.gca() 
my_axis.set_xlim(0,5) 
for p in set(h.findobj(lambda x: x.get_gid()=='dummy')): 
    p.set_ydata(np.ones(10)*10.0) 
plt.show() 

注意，在plt.plot的gid參數通常使用matplotlib（僅）當後端被設置爲 'SVG'。它使用gid作爲id屬性給一些分組元素（如line2d,patch,text）。

Answer 2

我沒有使用MATLAB，但我認爲這是你想要的

import matplotlib 
import matplotlib.pyplot as plt 

x = [1,3,4,5,6] 
y = [1,9,16,25,36] 
fig = plt.figure() 
ax = fig.add_subplot(111) # add a plot 
ax.set_title('y = x^2') 
line1, = ax.plot(x, y, 'o-')  #x1,y1 are lists(equal size) 
line1.set_ydata(y2)    #Use this to modify Ydata 
plt.show() 

當然，這僅僅是一個基本的情節，還有更多的it.Go雖然this找到圖你想要查看它的源代碼。

Answer 3

# create figure and return figure handle 
h = figure() 

# add a plot but tagging like matlab is not available here. But you can 
# set one of the attributes to find it later. url seems harmless to modify. 
# plot() returns a list of Line2D instances which you can store in a variable 
p = plot(arange(1,11), arange(1,11), url='my_tag') 

# add a legend 
my_legend = legend(p,('a line',)) 
# you could also do 
# p = plot(arange(1,11), arange(1,11), label='a line', url='my_tag') 
# legend() 
# or 
# p[0].set_label('a line') 
# legend() 

# change figure name: not sure what this is for. 
# set(h, 'name', 'myfigure') 

# find current axes 
my_axis = gca() 
# change xlimits 
my_axis.set_xlim(0, 5) 
# You could compress the above two lines of code into: 
# xlim(start, end) 

# find the plot object generated above and modify YData 
# findobj in matplotlib needs you to write a boolean function to 
# match selection criteria. 
# Here we use a lambda function to return only Line2D objects 
# with the url property set to 'my_tag' 
q = h.findobj(lambda x: isinstance(x, Line2D) and x.get_url() == 'my_tag') 

# findobj returns duplicate objects in the list. We can take the first entry. 
q[0].set_ydata(ones(10)*10.0) 

# now refresh the figure 
draw()