Merge branch 'master' of https://github.com/like2000/PyHEADTAIL into losses

Author: michuschenk

_version.py

@@ -1,2 +1,2 @@
-__version__ = "1.0.4"
+__version__ = "1.0.8"
 

feedback/__init__.py

@@ -0,0 +1 @@
+from .. import __version__

feedback/transverse_damper.py

@@ -0,0 +1,44 @@
+'''
+@author Kevin Li
+@date 20/06/2014
+@copyright CERN
+'''
+from __future__ import division
+
+
+import numpy as np
+from scipy.special import k0
+from scipy.constants import c, e
+import pylab as plt
+
+
+class TransverseDamper(object):
+
+    def __init__(self, dampingrate_x, dampingrate_y):
+        self.gain_x = 2/dampingrate_x
+        self.gain_y = 2/dampingrate_y
+
+        if dampingrate_x and not dampingrate_y:
+            self.track = self.track_horizontal
+        elif not dampingrate_x and dampingrate_y:
+            self.track = self.track_vertical
+        else:
+            self.track = self.track_all
+
+    def track_horizontal(self, beam):
+        beam.xp -= self.gain_x * beam.mean_xp()
+
+    def track_vertical(self, beam):
+        beam.yp -= self.gain_y * beam.mean_yp()
+
+    def track_all(self, beam):
+        beam.xp -= self.gain_x * beam.mean_xp()
+        beam.yp -= self.gain_y * beam.mean_yp()
+
+    @classmethod
+    def horizontal(cls, dampingrate_x):
+        return cls(dampingrate_x, 0)
+
+    @classmethod
+    def vertical(cls, dampingrate_y):
+        return cls(0, dampingrate_y)