From 895724218d77c29357cb0f7e7a44895e456d9e39 Mon Sep 17 00:00:00 2001
From: Anton Akhmerov <anton.akhmerov@gmail.com>
Date: Mon, 4 May 2015 01:25:37 +0200
Subject: [PATCH] clarify handling of old numpy versions
---
kwant/physics/leads.py | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)
diff --git a/kwant/physics/leads.py b/kwant/physics/leads.py
index 76d016ee..c2003ad2 100644
--- a/kwant/physics/leads.py
+++ b/kwant/physics/leads.py
@@ -20,6 +20,19 @@ dot = np.dot
__all__ = ['selfenergy', 'modes', 'PropagatingModes', 'StabilizedModes']
+if np.__version__ >= '1.8':
+ complex_any = np.any
+else:
+ def complex_any(array):
+ """Check if a complex array has nonzero entries.
+
+ This function is needed due to a bug in numpy<1.8.
+ """
+ # TODO: Remove separate checking of real and imaginary parts once we depend
+ # on numpy>=1.8 (it is present due to a bug in earlier versions).
+ return np.any(array.real) or np.any(array.imag)
+
+
# Container classes
Linsys = namedtuple('Linsys', ['eigenproblem', 'v', 'extract'])
@@ -162,11 +175,9 @@ def setup_linsys(h_cell, h_hop, tol=1e6, stabilization=None):
if stabilization is not None:
stabilization = list(stabilization)
- if not (np.any(h_hop.real) or np.any(h_hop.imag)):
+ if not complex_any(h_hop):
# Inter-cell hopping is zero. The current algorithm is not suited to
# treat this extremely singular case.
- # Note: np.any(h_hop) returns (at least from numpy 1.6.*)
- # False if h_hop is purely imaginary
raise ValueError("Inter-cell hopping is exactly zero.")
# If both h and t are real, it may be possible to use the real eigenproblem.
@@ -495,8 +506,7 @@ def make_proper_modes(lmbdainv, psi, extract, tol=1e6):
order = np.lexsort([velocities, -np.sign(velocities) * momenta,
np.sign(velocities)])
- # The following is necessary due to wrong numpy handling of zero length
- # arrays, which is going to be fixed in numpy 1.8.
+ # TODO: Remove the check once we depende on numpy>=1.8.
if not len(order):
order = slice(None)
velocities = velocities[order]
@@ -567,9 +577,7 @@ def modes(h_cell, h_hop, tol=1e6, stabilization=None):
h_cell.shape[0] != h_hop.shape[0]):
raise ValueError("Incompatible matrix sizes for h_cell and h_hop.")
- # Note: np.any(h_hop) returns (at least from numpy 1.6.1 - 1.8-devel)
- # False if h_hop is purely imaginary
- if not (np.any(h_hop.real) or np.any(h_hop.imag)):
+ if not complex_any(h_hop):
v = np.empty((0, m))
return (PropagatingModes(np.empty((0, n)), np.empty((0,)),
np.empty((0,))),
--
GitLab