matlab -> python translation IterateMonitor

proxtoolbox/Algorithms/IterateMonitor.py

+from numpy.linalg import norm
+from numpy import sqrt
+
+
 class IterateMonitor:
-    def __init__(self,config):
+    def __init__(self, config):
         self.norm_data = config['norm_data']
-        #this will be set after the first call of monitor
+        # this will be set after the first call of monitor
         self.u_monitor = None
 
-    def monitor(u):
-        #check if u_monitor is set, otherwise first call of monitor
+    def monitor(self, u):
+        # check if u_monitor is set, otherwise first call of monitor
         if u.monitor == None:
-            #if first call, set change to high value
+            # if first call, set change to high value
             return 999
-        #this is the right calculation for change if u does not have blocks structure
+        # this is the right calculation for change if u does not have blocks structure
         if u.ndim < 3:
-            tmp_change= (norm(u-u_monitor, 'fro')/norm_data)**2 # What function are we trying to import here?
+            tmp_change = (norm(u - self.u_monitor,
+                               'fro') / self.norm_data) ** 2  # What function are we trying to import here?
         elif u.ndim == 3:
             for j in range(u.shape[2]):
-                tmp_change= tmp_change+ (norm(u[:,:,j]-u_monitor[:,:,j], 'fro')/norm_data)**2
+                tmp_change = tmp_change + (norm(u[:, :, j] - self.u_monitor[:, :, j], 'fro') / self.norm_data) ** 2
         else:
             for j in range(u.shape[3]):
-              for k in range(u.shape[2]:
-                tmp_change= tmp_change+ (norm(u[:,:,k,j]-u_monitor[:,:,k,j], 'fro')/norm_data)**2
+                for k in range(u.shape[2]):
+                    tmp_change = tmp_change + (
+                                norm(u[:, :, k, j] - self.u_monitor[:, :, k, j], 'fro') / self.norm_data) ** 2
 
         change = sqrt(tmp_change)
-        #hopefully copies to config
+        # hopefully copies to config
         self.u_monitor = u
 
         return change