def bloch(ex_values, tlist, ops):
"""Plots expectation values of sx, sy and sz on the Bloch sphere.
If one of these operators is not calculated, zeros are passed for that operator.
Parameters:
-----------
ex_values : qutip.Result.expect or list
expectation values per operator
tlist : list, or numpy array
times at which expectation values are evaluated
ops : list
operators of which the expectation values are found in ex_values
Remark:
-------
Does not plot a color bar yet. The lines from the QuTiP tutorial (https://nbviewer.jupyter.org/github/qutip/qutip-notebooks/blob/master/examples/bloch_sphere_with_colorbar.ipynb), commented out down here, give an error which I have not been able to solve yet.
"""
if 'sx' in ops:
sx_exp = ex_values[ops.index('sx')]
elif 'sx' not in ops:
sx_exp = np.zeros(len(list(tlist)))
if 'sy' in ops:
sy_exp = ex_values[ops.index('sy')]
elif 'sy' not in ops:
sy_exp = np.zeros(len(list(tlist)))
if 'sz' in ops:
sz_exp = ex_values[ops.index('sz')]
elif 'sz' not in ops:
sz_exp = np.zeros(len(list(tlist)))
b = Bloch()
b.add_points([sx_exp, sy_exp, sz_exp], 'm')
nrm = Normalize(-2,10)
colors = cm.hot(nrm(tlist))
b.point_color = list(colors)
b.point_marker = ['o']
# TODO: Plot color bar
# left, bottom, width, height = [0.98, 0.05, 0.05, 0.9]
# ax2 = b.fig.add_axes([left, bottom, width, height])
# ColorbarBase(ax2, cmap=cm.hot, norm=nrm, orientation='vertical')
b.show()
def plot_point_test(self, fig, point_kws):
b = Bloch(fig=fig)
for kw in point_kws:
points = kw.pop("points")
b.add_points(points, **kw)
b.render()