def trace_cython(B, nr_procs, force_subprocess=False):
lines, topo = streamline.streamlines(B, vol, ds0=0.02, ibound=3.7,
maxit=5000, output=streamline.OUTPUT_BOTH,
method=streamline.EULER1,
tol_lo=0.005, tol_hi=0.1,
fac_refine=0.75, fac_coarsen=1.5,
nr_procs=nr_procs,
force_subprocess=force_subprocess)
return lines, topo
def trace_cython(fld_bx, fld_by, fld_bz):
# print("Cython...")
B = field.scalar_fields_to_vector([fld_bx, fld_by, fld_bz], name="B_cc",
_force_layout=field.LAYOUT_INTERLACED)
t0 = time()
lines, topo = None, None
lines, topo = streamline.streamlines(B, vol, ds0=0.02, ibound=3.7,
maxit=5000, output=streamline.OUTPUT_BOTH,
method=streamline.EULER1,
tol_lo=0.005, tol_hi=0.1,
fac_refine=0.75, fac_coarsen=1.5)
t1 = time()
topo_fld = vol.wrap_field(topo, name="CyTopo")
# cmap = plt.get_cmap('spectral')
# levels = [4, 5, 6, 7, 8, 13, 14, 16, 17]
# norm = BoundaryNorm(levels, cmap.N)
# mpl.plot(topo_fld, "y=0", cmap=cmap, norm=norm, show=False)
# # mpl.plot_streamlines2d(lines[::5], "y", topology=topo[::5], show=False)
# # mpl.plot_streamlines(lines, topology=topo, show=False)
# mpl.mplshow()
# topo_src = mvi.add_field(topo_fld, center='node')
# mvi.plot_lines(mlab.pipeline, lines[::5], topo[::5], opacity=0.8,
# tube_radius=0.02)
# mvi.plod_earth_3d(mlab.pipeline)
# mlab.show()
nsegs = 1 # keep from divding by 0 is no streamlines
if lines is not None:
nsegs = 0
for line in lines:
nsegs += len(line[0])
t = t1 - t0
print("total segments calculated: ", nsegs)
print("time: {0:.4}s ... {1:.4}s/segment".format(t, t / float(nsegs)))
return lines, topo_fld
def main():
parser = argparse.ArgumentParser(description="Streamline a PSC file")
parser.add_argument("-t", default="2000",
help="which time to plot (finds closest)")
parser.add_argument('infile', nargs=1, help='input file')
args = vutil.common_argparse(parser)
# f = readers.load_file("pfd.020000.xdmf")
# ... or ...
# using this way of loading files, one probably wants just to give
# pfd.xdmf to the command line
f = readers.load_file(args.infile[0])
f.activate_time(args.t)
jz = f["jz"]
# recreate hx as a field of 0 to keep streamlines from moving in
# that direction
hx = field.zeros_like(jz, name="hx")
h1 = field.scalar_fields_to_vector([hx, f["hy"], f["hz"]], name="H",
_force_layout="Interlaced",
forget_source=True)
e = field.scalar_fields_to_vector([f["ex"], f["ey"], f["ez"]], name="E",
_force_layout="Interlaced",
forget_source=True)
# plot magnetic fields, just a sanity check
# ax1 = plt.subplot(211)
# mpl.plot(f["hy"], flip_plot=True)
# ax2 = plt.subplot(212, sharex=ax1, sharey=ax1)
# mpl.plot(f["hz"], flip_plot=True)
# mpl.mplshow()
# make a line of 30 seeds straight along the z axis (x, y, z ordered)
seeds1 = seed.Line((0.0, 0.0, 2.0), (1022.0, 0.0, 0.0), 60)
# set outer boundary limits for streamlines
ds = 0.005 # spatial step along the stream line curve
obound0 = np.array([1, -128, -1000], dtype=h1.dtype)
obound1 = np.array([1023, 128, 1000], dtype=h1.dtype)
# calc the streamlines
lines1, topo1 = streamline.streamlines(h1, seeds1, ds0=ds, maxit=200000,
obound0=obound0, obound1=obound1,
ibound=0.0)
# run with -v to see this
logger.info("Topology flags: {0}".format(topo1))
# rotate plot puts the z axis along the horizontal
flip_plot = True
mpl.plot(jz, flip_plot=flip_plot, plot_opts="lin_-.05_.05")
# mpl.plot_streamlines2d(lines1, "x", flip_plot=flip_plot, color='k')
plt.xlim([0, 1024])
plt.ylim([-128, 128])
plt.show()
# interpolate e onto each point of the first field line of lines1
e1 = cycalc.interp_trilin(e, seed.Point(lines1[0]))
print(e1.shape, lines1[0].shape)
plt.clf()
plt.plot(np.linspace(0, ds * e1.shape[0], e1.shape[0]), e1[:, 0])
plt.xlabel("length along field line")
plt.ylabel("Ex")
plt.show()
return 0
