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x axis inverts when using plot with negative y #300
Description
Description
within cartesian grid, using plot, x axis inverts with y set starting with nagative number
Steps to reproduce
import numpy as np
import proplot as pplt
print(pplt.version)
fig = pplt.figure(suptitle='test')
ax = fig.subplot(111, title="A-B")
ax.format(xlim=(-2, 2),
xticks=0.5,
xloc=('data', -2),
xlabel='x axis',
xlabelloc='bottom',
ylim=(-2, 2),
yticks=0.5,
yloc=('data', -2),
ylabel='y axis')
ax.set_aspect('equal')
ax.scatter(-1, 1, color="b")
ax.text(-1, 1, "A")
ax.scatter(1, -1, color="b")
ax.text(1, -1, "B")
x_set = [-1, 1]
y_set = [1, -1]
ax.plot(x_set, y_set, color="r")
pplt.show()
Expected behavior:
The above code gives a grid as expected, with the 2 points A and B and a red line between them
Actual behavior: [What actually happened]
However, when changing the x_set/y_set lines to
x_set = [1, -1]
y_set = [-1, 1]
the x-axis inverts (i.e. the whole grid) starting with x = 2 going to x = -2
Equivalent steps in matplotlib
with ax.invert_xaxis() the grid inverts to the presentation as expected
Proplot version 0.9.5
Paste the results of import matplotlib; print(matplotlib.__version__); import proplot; print(proplot.version)here.
Activity
dewinkelwaar commentedon Nov 2, 2021
Note that this issue doesn`t occur when using matplotlib
import numpy as np
import matplotlib.pyplot as plt
fig = plt.figure()
ax = plt.subplot()
ax.set_xlim(-2, 2)
ax.set_ylim(-2, 2)
ax.set_title('line plot A->B vs B->A')
ax.set_xlabel('x axis')
ax.set_ylabel('y axis')
ax.scatter(-1, 1, color="b")
ax.text(-1, 1, "A")
ax.scatter(1, -1, color="b")
ax.text(1, -1, "B")
#x_set = [-1, 1]
#y_set = [1, -1]
x_set = [1, -1]
y_set = [-1, 1]
ax.plot(x_set, y_set, color="r")
pplt.show()
lukelbd commentedon Nov 2, 2021
This is part of the "standardized arguments" feature (see this link)... but unfortunately I did not document it! I'll add this to the docs in the next version.
I find that most of the time, when I have "reversed" dependent variable coordinates, I want that axis to be reversed too. So I think I'd prefer to keep this default behavior. In your example, you can use
ax.format(xreverse=False)to reverse the axis back. Alternatively (this is currently not part of the public API)ax.plot(x_set, y_set, autoreverse=False)should also work. Might make that part of the public API in the future.dewinkelwaar commentedon Nov 3, 2021
Ok, I understand your point. Thanks for the reply
Add 'autoreverse' docs and disable when lims are fixed (closes #300)
lukelbd commentedon Nov 3, 2021
No problem. FYI the master branch now includes documentation on auto-reversing in the "1D plotting" and "2D plotting" sections, and auto-reversing is now automatically disabled whenever the axis limits were previously explicitly fixed with e.g.
ax.format(xlim=xlim)orax.set_xlim(xlim)(f34c12c).