On Mon, Mar 8, 2010 at 6:52 AM, Bruce Southey <bsout...@gmail.com
<mailto:bsout...@gmail.com>> wrote:
On 03/08/2010 01:30 AM, David Goldsmith wrote:
On Sun, Mar 7, 2010 at 4:41 AM, Friedrich Romstedt
<friedrichromst...@gmail.com
<mailto:friedrichromst...@gmail.com>> wrote:
I would like to stress the fact that imo this is maybe not
ticket and not a bug.
The issue arises when calling a.max() or similar of empty
arrays a, i.e., with:
>>> 0 in a.shape
True
Opposed to the .prod() of an empty array, such a .max() or .min()
cannot be defined, because the set is empty. So it's fully
correct to
let such calls fail. Just the failure is a bit deep in
numpy, and
only the traceback gives some hint what went wrong.
I posted something similar also on the matplotlib-users list,
sorry
for cross-posting thus.
Any suggestions, then, how to go about figuring out what's
happening in my code that's causing this "feature" to manifest
itself?
DG
Perhaps providing the code with specific versions of Python, numpy
etc. would help.
I would guess that aquarius_test.py has not correctly setup the
necessary inputs (or has invalid inputs) required by matplotlib
(which I have no knowledge about). Really you have to find if the
_A in cmp.py used by 'self.norm.autoscale_None(self._A)' is valid.
You may be missing a valid initialization step because the
TypeError exception in autoscale_None ('You must first set_array
for mappable') implies something need to be done first.
Bruce
Python 2.5.4, Numpy 1.4.0, Matplotlib 0.99.0, Windows 32bit Vista Home
Premium SP2
# Code copyright 2010 by David Goldsmith
# Comments and unnecessaries edited for brevity
import numpy as N
import matplotlib as MPL
from matplotlib import pylab
from matplotlib.backends.backend_agg import FigureCanvasAgg as
FigureCanvas
from matplotlib.figure import Figure
import matplotlib.cm <http://matplotlib.cm> as cm
J = complex(0,1); tol = 1e-6; maxiter = 20;
roots = (-2 + J/2, -1 + J, -0.5 + J/2, 0.5 + J, 1 + J/2, 2 + J, 2.5
+ J/2,
-2 - J, -1 - J/2, -0.5 - J, 0.5 - J/2, 1 - J, 2 - J/2,
2.5 - J)
def ffp(z):
w, wp = (0J, 0J)
for root in roots:
z0 = z - root
w += N.sin(1/z0)
wp -= N.cos(1/z0)/(z0*z0)
return (w, wp)
def iter(z):
w, wp = ffp(z)
return z - w/wp
def find_root(z0):#, k, j):
count = 0
z1 = iter(z0)
if N.isnan(z1):
return N.complex64(N.inf)
while (N.abs(z1 - z0) > tol) and \
(count < maxiter):
count += 1
z0 = z1
z1 = iter(z0)
if N.abs(z1 - z0) > tol:
result = 0
else:
result = z1
return N.complex64(result)
w, h, DPI = (3.2, 2.0, 100)
fig = Figure(figsize=(w, h),
dpi=DPI,
frameon=False)
ax = fig.add_subplot(1,1,1)
canvas = FigureCanvas(fig)
nx, xmin, xmax = (int(w*DPI), -0.5, 0.5)
ny, ymin, ymax = (int(h*DPI), 0.6, 1.2)
X, xincr = N.linspace(xmin,xmax,nx,retstep=True)
Y, yincr = N.linspace(ymin,ymax,ny,retstep=True)
W = N.zeros((ny,nx), dtype=N.complex64)
for j in N.arange(nx):
if not (j%100): # report progress
print j
for k in N.arange(ny):
x, y = (X[j], Y[k])
z0 = x + J*y
W[k,j] = find_root(z0)#,k,j)
print N.argwhere(N.logical_not(N.isfinite(W.real)))
print N.argwhere(N.logical_not(N.isfinite(W.imag)))
W = W.T
argW = N.angle(W)
print N.argwhere(N.logical_not(N.isfinite(argW)))
cms = ("Blues",)# "Blues_r", "cool", "cool_r",
def all_ticks_off(ax):
ax.xaxis.set_major_locator(pylab.NullLocator())
ax.yaxis.set_major_locator(pylab.NullLocator())
for cmap_name in cms:
all_ticks_off(ax)
ax.hold(True)
for i in range(4):
for j in range(4):
part2plot = argW[j*ny/4:(j+1)*ny/4, i*nx/4:(i+1)*nx/4]
if N.any(N.logical_not(N.isfinite(part2plot))):
print i, j,
print N.argwhere(N.logical_not(N.isfinite(part2plot)))
extent = (i*nx/4, (i+1)*nx/4, (j+1)*ny/4, j*ny/4)
ax.imshow(part2plot, cmap_name, extent = extent)
ax.set_xlim(0, nx)
ax.set_ylim(0, ny)
canvas.print_figure('../../Data-Figures/Zodiac/Aquarius/'+ cmap_name +
'Aquarius_test.png', dpi=DPI)
# End Aquarius_test.png
DG
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