我正在尝试将数据点从数据坐标系转换为 matplotlib 中的轴坐标系。
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
# this is in data coordinates
point = (1000, 1000)
# this takes us from the data coordinates to the display coordinates.
trans = ax.transData.transform(point)
print(trans) # so far so good.
# this should take us from the display coordinates to the axes coordinates.
trans = ax.transAxes.inverted().transform(trans)
# the same but in one line
# trans = (ax.transData + ax.transAxes.inverted()).transform(point)
print(trans) # why did it transform back to the data coordinates? it
# returns [1000, 1000], while I expected [0.5, 0.5]
ax.set_xlim(0, 2000)
ax.set_ylim(0, 2000)
ax.plot(*trans, 'o', transform=ax.transAxes)
# ax.plot(*point, 'o')
fig.show()
我读了transformation tutorial并尝试了 this answer 中提供的解决方案,我的代码基于它,但它不起作用。我只是想不通为什么,这让我发疯。我确信有一个简单的解决方案,但我只是没有看到。
最佳答案
转换正在运行,只是当您开始时,默认轴限制为 0、1,并且它不会提前知道您打算更改限制:
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
# this is in data coordinates
point = (1000, 1000)
trans = ax.transData.transform(point)
trans = ax.transAxes.inverted().transform(trans)
print(ax.get_xlim(), trans)
ax.set_xlim(0, 2000)
ax.set_ylim(0, 2000)
trans = ax.transData.transform(point)
trans = ax.transAxes.inverted().transform(trans)
print(ax.get_xlim(), trans)
产量:
(0.0, 1.0) [1000. 1000.]
(0.0, 2000.0) [0.5 0.5]
关于python - 在 matplotlib 中将数据坐标转换为轴坐标,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/62004022/