sineefit: Change sfit4 to fit to \sin instead of \cos

And adjust the period locator accordingly.
Fitting \sin is the same mathematically, it's just conceptually more
straightforward since we're locating zero crossings anyway.

setup.py

@@ -61,7 +61,7 @@ setup(name='nilmtools',
       long_description = "NILM Database Tools",
       license = "Proprietary",
       author_email = 'jim@jtan.com',
-      install_requires = [ 'nilmdb >= 1.5.0',
+      install_requires = [ 'nilmdb >= 1.6.0',
                            'numpy',
                            'scipy',
                            'matplotlib',

src/cleanup.py

@@ -238,12 +238,15 @@ def main(argv = None):
                        timestamp_to_seconds(total)))
             continue
         printf("  removing data before %s\n", timestamp_to_human(remove_before))
+        # Clean in reverse order.  Since we only use the primary stream and not
+        # the decimated streams to figure out which data to remove, removing
+        # the primary stream last means that we might recover more nicely if
+        # we are interrupted and restarted.
+        clean_paths = list(reversed(streams[path].also_clean_paths)) + [ path ]
+        for p in clean_paths:
+            printf("  removing from %s\n", p)
             if args.yes:
-            client.stream_remove(path, None, remove_before)
+                client.stream_remove(p, None, remove_before)
-        for ap in streams[path].also_clean_paths:
-            printf("  also removing from %s\n", ap)
-            if args.yes:
-                client.stream_remove(ap, None, remove_before)
 
     # All done
     if not args.yes:

src/filter.py

@@ -67,7 +67,7 @@ def get_stream_info(client, path):
 
 class Filter(object):
 
-    def __init__(self):
+    def __init__(self, parser_description = None):
         self._parser = None
         self._client_src = None
         self._client_dest = None
@@ -78,6 +78,9 @@ class Filter(object):
         self.end = None
         self.interhost = False
         self.force_metadata = False
+        if parser_description is not None:
+            self.setup_parser(parser_description)
+            self.parse_args()
 
     @property
     def client_src(self):
@@ -275,6 +278,10 @@ class Filter(object):
         Return value of 'function' is the number of data rows processed.
         Unprocessed data will be provided again in a subsequent call
         (unless 'final' is True).
+
+        If unprocessed data remains after 'final' is True, the interval
+        being inserted will be ended at the timestamp of the first
+        unprocessed data point.
         """
         if args is None:
             args = []
@@ -319,7 +326,13 @@ class Filter(object):
 
                 # Last call for this contiguous interval
                 if old_array.shape[0] != 0:
-                    function(old_array, interval, args, insert_function, True)
+                    processed = function(old_array, interval, args,
+                                         insert_function, True)
+                    if processed != old_array.shape[0]:
+                        # Truncate the interval we're inserting at the first
+                        # unprocessed data point.  This ensures that
+                        # we'll not miss any data when we run again later.
+                        insert_ctx.update_end(old_array[processed][0])
 
 def main(argv = None):
     # This is just a dummy function; actual filters can use the other

src/sinefit.py

@@ -98,12 +98,12 @@ def process(data, interval, args, insert_function, final):
             continue
 
         #p.plot(arange(N), this)
-        #p.plot(arange(N), A * cos(f0/fs * 2 * pi * arange(N) + phi) + C, 'g')
+        #p.plot(arange(N), A * sin(f0/fs * 2 * pi * arange(N) + phi) + C, 'g')
 
-        # Period starts when the argument of cosine is 3*pi/2 degrees,
+        # Period starts when the argument of sine is 0 degrees,
         # so we're looking for sample number:
-        #     n = (3 * pi / 2 - phi) / (f0/fs * 2 * pi)
+        #     n = (0 - phi) / (f0/fs * 2 * pi)
-        zc_n = (3 * pi / 2 - phi) / (f0 / fs * 2 * pi)
+        zc_n = (0 - phi) / (f0 / fs * 2 * pi)
         period_n = fs/f0
 
         # Add periods to make N positive
@@ -149,15 +149,15 @@ def sfit4(data, fs):
 
     Output:
       Parameters [A, f0,  phi, C] to fit the equation
-        x[n] = A * cos(f0/fs * 2 * pi * n + phi) + C
+        x[n] = A * sin(f0/fs * 2 * pi * n + phi) + C
       where n is sample number.  Or, as a function of time:
-        x(t) = A * cos(f0 * 2 * pi * t + phi) + C
+        x(t) = A * sin(f0 * 2 * pi * t + phi) + C
 
     by Jim Paris
     (Verified to match sfit4.m)
     """
     N = len(data)
-    t = linspace(0, (N-1) / fs, N)
+    t = linspace(0, (N-1) / float(fs), N)
 
     ## Estimate frequency using FFT (step b)
     Fc = fft(data)
@@ -182,18 +182,17 @@ def sfit4(data, fs):
     i = arccos((Z2*cos(ni2) - Z1*cos(ni1)) / (Z2-Z1)) / n
 
     # Convert to Hz
-    f0 = i * fs / N
+    f0 = i * float(fs) / N
 
     # Fit it.  We'll catch exceptions here and just returns zeros
     # if something fails with the least squares fit, etc.
     try:
         # first guess for A0, B0 using 3-parameter fit (step c)
+        s = zeros(3)
         w = 2*pi*f0
-        D = c_[cos(w*t), sin(w*t), ones(N)]
-        s = linalg.lstsq(D, data)[0]
 
-        # Now iterate 6 times (step i)
+        # Now iterate 7 times (step b, plus 6 iterations of step i)
-        for idx in range(6):
+        for idx in range(7):
             D = c_[cos(w*t), sin(w*t), ones(N),
                   -s[0] * t * sin(w*t) + s[1] * t * cos(w*t) ] # eqn B.16
             s = linalg.lstsq(D, data)[0] # eqn B.18
@@ -202,7 +201,7 @@ def sfit4(data, fs):
         ## Extract results
         A = sqrt(s[0]*s[0] + s[1]*s[1]) # eqn B.21
         f0 = w / (2*pi)
-        phi = -arctan2(s[1], s[0]) # eqn B.22
+        phi = arctan2(s[0], s[1]) # eqn B.22 (flipped for sin instead of cos)
         C = s[2]
         return (A, f0, phi, C)
     except Exception as e: