espressopp.analysis.PressureTensorMultiLayer¶
This class computes the pressure tensor of the system in n layers. Layers are perpendicular to Z direction and are equidistant(distance is Lz/n). It can be used as standalone class in python as well as in combination with the integrator extension ExtAnalyze.
Example of standalone Usage:
>>> pt = espressopp.analysis.PressureTensorMultiLayer(system, n, dh)
>>> for i in xrange(n):
>>> print "pressure tensor in layer %d: %s" % ( i, pt.compute())
or
>>> pt = espressopp.analysis.PressureTensorMultiLayer(system, n, dh)
>>> for k in xrange(100):
>>> integrator.run(100)
>>> pt.performMeasurement()
>>> for i in xrange(n):
>>> print "average pressure tensor in layer %d: %s" % ( i, pt.compute())
Example of usage in integrator with ExtAnalyze:
>>> pt = espressopp.analysis.PressureTensorMultiLayer(system, n, dh)
>>> extension_pt = espressopp.integrator.ExtAnalyze(pt , interval=100)
>>> integrator.addExtension(extension_pt)
>>> integrator.run(10000)
>>> pt_ave = pt.getAverageValue()
>>> for i in xrange(n):
>>> print "average Pressure Tensor = ", pt_ave[i][:6]
>>> print " std deviation = ", pt_ave[i][6:]
>>> print "number of measurements = ", pt.getNumberOfMeasurements()
The following methods are supported:
 performMeasurement()
 computes the pressure tensor and updates average and standard deviation
 reset()
 resets average and standard deviation to 0
 compute()
 computes the instant pressure tensor in n layers, return value: [xx, yy, zz, xy, xz, yz]
 getAverageValue()
 returns the average pressure tensor and the standard deviation, return value: [xx, yy, zz, xy, xz, yz, +xx, +yy, +zz, +xy, +xz, +yz]
 getNumberOfMeasurements()
 counts the number of measurements that have been computed (standalone or in integrator) does _not_ include measurements that have been done using “compute()”

espressopp.analysis.
PressureTensorMultiLayer
(system, n, dh)¶ Parameters:  system –
 n –
 dh –