def curvelinear_test2(fig):
"""
Polar projection, but in a rectangular box.
"""
# PolarAxes.PolarTransform takes radian. However, we want our coordinate
# system in degree
tr = Affine2D().scale(np.pi / 180, 1) + PolarAxes.PolarTransform()
# Polar projection, which involves cycle, and also has limits in
# its coordinates, needs a special method to find the extremes
# (min, max of the coordinate within the view).
extreme_finder = angle_helper.ExtremeFinderCycle(
nx=20,
ny=20, # Number of sampling points in each direction.
lon_cycle=360,
lat_cycle=None,
lon_minmax=None,
lat_minmax=(0, np.inf),
)
# Find grid values appropriate for the coordinate (degree, minute, second).
grid_locator1 = angle_helper.LocatorDMS(12)
# Use an appropriate formatter. Note that the acceptable Locator and
# Formatter classes are a bit different than that of Matplotlib, which
# cannot directly be used here (this may be possible in the future).
tick_formatter1 = angle_helper.FormatterDMS()
grid_helper = GridHelperCurveLinear(tr,
extreme_finder=extreme_finder,
grid_locator1=grid_locator1,
tick_formatter1=tick_formatter1)
ax1 = fig.add_subplot(1,
2,
2,
axes_class=HostAxes,
grid_helper=grid_helper)
# make ticklabels of right and top axis visible.
ax1.axis["right"].major_ticklabels.set_visible(True)
ax1.axis["top"].major_ticklabels.set_visible(True)
# let right axis shows ticklabels for 1st coordinate (angle)
ax1.axis["right"].get_helper().nth_coord_ticks = 0
# let bottom axis shows ticklabels for 2nd coordinate (radius)
ax1.axis["bottom"].get_helper().nth_coord_ticks = 1
ax1.set_aspect(1)
ax1.set_xlim(-5, 12)
ax1.set_ylim(-5, 10)
ax1.grid(True, zorder=0)
# A parasite axes with given transform
ax2 = ParasiteAxesAuxTrans(ax1, tr, "equal")
# note that ax2.transData == tr + ax1.transData
# Anything you draw in ax2 will match the ticks and grids of ax1.
ax1.parasites.append(ax2)
ax2.plot(np.linspace(0, 30, 51), np.linspace(10, 10, 51), linewidth=2)
ax2.pcolor(np.linspace(0, 90, 4), np.linspace(0, 10, 4),
np.arange(9).reshape((3, 3)))
ax2.contour(np.linspace(0, 90, 4),
np.linspace(0, 10, 4),
np.arange(16).reshape((4, 4)),
colors="k")