Author: bugman
Date: Fri Jul 12 17:12:38 2013
New Revision: 20285
URL: http://svn.gna.org/viewcvs/relax?rev=20285&view=rev
Log:
Added the missing mpower() function as
lib.linear_algebra.matrix_power.square_matrix_power().
This is needed by the lib.dispersion.ns_2site_star module.
The function comes from the 'fitting_main_kex.py' file attached to comment 3
of task #7712
(https://gna.org/task/?7712#comment3,
https://gna.org/support/download.php?file_id=18263).
The mpower() function was copied and modified to suite relax's coding
conventions.
Added:
branches/relax_disp/lib/linear_algebra/matrix_power.py
Modified:
branches/relax_disp/lib/dispersion/ns_2site_star.py
branches/relax_disp/lib/linear_algebra/__init__.py
Modified: branches/relax_disp/lib/dispersion/ns_2site_star.py
URL:
http://svn.gna.org/viewcvs/relax/branches/relax_disp/lib/dispersion/ns_2site_star.py?rev=20285&r1=20284&r2=20285&view=diff
==============================================================================
--- branches/relax_disp/lib/dispersion/ns_2site_star.py (original)
+++ branches/relax_disp/lib/dispersion/ns_2site_star.py Fri Jul 12 17:12:38
2013
@@ -36,6 +36,9 @@
from numpy import conj, dot, matrix
if dep_check.scipy_module:
from scipy.linalg import expm
+
+# relax module imports.
+from lib.linear_algebra.matrix_power import square_matrix_power
def r2eff_ns_2site_star(r20a=None, r20b=None, fg=None, kge=None, keg=None,
tcpmg=None, cpmg_frqs=None, back_calc=None, num_points=None):
@@ -87,7 +90,7 @@
prop_2 = dot(dot(expm_R_tcp, expm(cR2*tcp)), expm_R_tcp)
- prop_total = mpower(prop_2, cpmg_frqs[i]*tcpmg)
+ prop_total = square_matrix_power(prop_2, cpmg_frqs[i]*tcpmg)
Moft = prop_total * M0
Modified: branches/relax_disp/lib/linear_algebra/__init__.py
URL:
http://svn.gna.org/viewcvs/relax/branches/relax_disp/lib/linear_algebra/__init__.py?rev=20285&r1=20284&r2=20285&view=diff
==============================================================================
--- branches/relax_disp/lib/linear_algebra/__init__.py (original)
+++ branches/relax_disp/lib/linear_algebra/__init__.py Fri Jul 12 17:12:38
2013
@@ -23,5 +23,6 @@
"""The relax-lib NMR package - a library of functions for advanced linear
algebra not present in numpy."""
__all__ = [
- 'kronecker_product'
+ 'kronecker_product',
+ 'matrix_power'
]
Added: branches/relax_disp/lib/linear_algebra/matrix_power.py
URL:
http://svn.gna.org/viewcvs/relax/branches/relax_disp/lib/linear_algebra/matrix_power.py?rev=20285&view=auto
==============================================================================
--- branches/relax_disp/lib/linear_algebra/matrix_power.py (added)
+++ branches/relax_disp/lib/linear_algebra/matrix_power.py Fri Jul 12
17:12:38 2013
@@ -1,0 +1,57 @@
+###############################################################################
+#
#
+# Copyright (C) 2013 Edward d'Auvergne
#
+#
#
+# This file is part of the program relax (http://www.nmr-relax.com).
#
+#
#
+# This program is free software: you can redistribute it and/or modify
#
+# it under the terms of the GNU General Public License as published by
#
+# the Free Software Foundation, either version 3 of the License, or
#
+# (at your option) any later version.
#
+#
#
+# This program is distributed in the hope that it will be useful,
#
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
#
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
#
+# GNU General Public License for more details.
#
+#
#
+# You should have received a copy of the GNU General Public License
#
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
+#
#
+###############################################################################
+
+
+# Python module imports.
+from numpy import diag, dot, eye
+from numpy.linalg import eig, inv
+
+# relax module imports.
+from lib.errors import RelaxError
+
+
+def square_matrix_power(x, y):
+ """Compute x raised to the power y when x is a square matrix and y is a
scalar.
+
+ @param x: The square matrix.
+ @type x: numpy rank-2 array
+ @param y: The power.
+ @type y: float
+ @return: The matrix power of x.
+ @rtype: numpy rank-2 array
+ """
+
+ # Sanity check.
+ s = x.shape()
+ if len(s) != 2 or s[0] != s[1]:
+ raise RelaxError("The matrix '%s' must be square." % x)
+
+ # Catch the zeroth power.
+ if y == 0:
+ return eye(s[0])
+
+ # The eigensystem of x.
+ e, v = eig(x)
+ d = diag(e)
+
+ # Return the matrix power.
+ return dot(dot(v, d**y), inv(v))
+
r20285 - in /branches/relax_disp/lib: dispersion/ns_2site_star.py linear_algebra/__init__.py linear_algebra/matrix_power.py