Add median filter

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.

Makefile

@@ -8,8 +8,11 @@ else
 	@echo "Try 'make install'"
 endif
 
-test:
-	src/decimate.py
+test: test_cleanup
+
+test_cleanup:
+	src/cleanup.py -e extras/cleanup.cfg
+	src/cleanup.py extras/cleanup.cfg
 
 test_insert:
 	@make install >/dev/null
@@ -21,12 +24,16 @@ test_copy:
 
 test_prep:
 	@make install >/dev/null
-	src/prep.py -c 3 \
-		/lees-compressor/no-leak/raw \
-		/lees-compressor/no-leak/sinefit \
-		/lees-compressor/no-leak/prep \
-	-s '2013-02-19 18:00:00' \
-	-r 0
+	-nilmtool destroy -R /test/raw
+	-nilmtool destroy -R /test/sinefit
+	-nilmtool destroy -R /test/prep
+	nilmtool create /test/raw float32_2
+	nilmtool create /test/sinefit float32_3
+	nilmtool create /test/prep float32_8
+	nilmtool insert -s '@0' -t -r 8000 /test/raw /tmp/raw.dat
+	src/sinefit.py -c 1 /test/raw /test/sinefit
+	src/prep.py -c 2 /test/raw /test/sinefit /test/prep
+	nilmtool extract -s min -e max /test/prep | head -20
 
 test_decimate:
 	-@nilmtool destroy /lees-compressor/no-leak/raw/4 || true

README.txt

@@ -5,10 +5,10 @@ by Jim Paris <jim@jtan.com>
 Prerequisites:
 
   # Runtime and build environments
-  sudo apt-get install python2.7 python2.7-dev python-setuptools
-  sudo apt-get install python-numpy python-scipy python-matplotlib
+  sudo apt-get install python2.7 python2.7-dev python-setuptools python-pip
+  sudo apt-get install python-numpy python-scipy
 
-  nilmdb (1.3.1+)
+  nilmdb (1.6.3+)
 
 Install:
 

extras/cleanup.cfg

@@ -0,0 +1,22 @@
+[/lees-compressor/no-leak/prep]
+keep = 2d
+rate = 60
+
+[*/raw]
+keep = 2d
+
+[*/something]
+rate = 10
+
+[*/sinefit]
+keep = 1w
+decimated = False
+
+[/test/raw]
+keep = 0.01d
+
+[/test/sinefit]
+keep = 0.01d
+
+[/test/prep]
+keep = 0.01d

setup.py

@@ -61,7 +61,7 @@ setup(name='nilmtools',
       long_description = "NILM Database Tools",
       license = "Proprietary",
       author_email = 'jim@jtan.com',
-      install_requires = [ 'nilmdb >= 1.4.6',
+      install_requires = [ 'nilmdb >= 1.6.0',
                            'numpy',
                            'scipy',
                            'matplotlib',
@@ -78,6 +78,8 @@ setup(name='nilmtools',
               'nilm-prep = nilmtools.prep:main',
               'nilm-copy-wildcard = nilmtools.copy_wildcard:main',
               'nilm-sinefit = nilmtools.sinefit:main',
+              'nilm-cleanup = nilmtools.cleanup:main',
+              'nilm-median = nilmtools.median:main',
               ],
           },
       zip_safe = False,

src/cleanup.py

@@ -0,0 +1,257 @@
+#!/usr/bin/python
+
+from nilmdb.utils.printf import *
+from nilmdb.utils.time import (parse_time, timestamp_to_human,
+                               timestamp_to_seconds, seconds_to_timestamp)
+from nilmdb.utils.diskusage import human_size
+from nilmdb.utils.interval import Interval
+import nilmdb.client
+import nilmdb.client.numpyclient
+import nilmtools
+import argparse
+import ConfigParser
+import sys
+import collections
+import fnmatch
+import re
+
+def warn(msg, *args):
+    fprintf(sys.stderr, "warning: " + msg + "\n", *args)
+
+class TimePeriod(object):
+    _units = { 'h': ('hour',  60*60),
+               'd': ('day',   60*60*24),
+               'w': ('week',  60*60*24*7),
+               'm': ('month', 60*60*24*30),
+               'y': ('year',  60*60*24*365) }
+
+    def __init__(self, val):
+        for u in self._units:
+            if val.endswith(u):
+                self.unit = self._units[u][0]
+                self.scale = self._units[u][1]
+                self.count = float(val[:-len(u)])
+                break
+        else:
+            raise ValueError("unknown units: " + units)
+
+    def seconds(self):
+        return self.count * self.scale
+
+    def describe_seconds(self, seconds):
+        count = seconds / self.scale
+        units = self.unit if count == 1 else (self.unit + "s")
+        if count == int(count):
+            return sprintf("%d %s", count, units)
+        else:
+            return sprintf("%.2f %s", count, units)
+
+    def __str__(self):
+        return self.describe_seconds(self.seconds())
+
+class StreamCleanupConfig(object):
+    def __init__(self, info):
+        self.path = info[0]
+        self.layout = info[1]
+        if info[4] != 0 and info[5] != 0:
+            self.rate = info[4] / timestamp_to_seconds(info[5])
+        else:
+            self.rate = None
+        self.keep = None
+        self.clean_decimated = True
+        self.decimated_from = None
+        self.also_clean_paths = []
+
+def main(argv = None):
+    parser = argparse.ArgumentParser(
+        formatter_class = argparse.RawDescriptionHelpFormatter,
+        version = nilmtools.__version__,
+        description = """\
+    Clean up old data from streams using a configuration file to specify
+    which data to remove.
+
+    The format of the config file is as follows:
+
+      [/stream/path]
+      keep = 3w         # keep up to 3 weeks of data
+      rate = 8000       # optional, used for the --estimate option
+      decimated = false # whether to delete decimated data too (default true)
+
+      [*/prep]
+      keep = 3.5m       # or 2520h or 105d or 15w or 0.29y
+
+    The suffix for 'keep' is 'h' for hours, 'd' for days, 'w' for weeks,
+    'm' for months, or 'y' for years.
+
+    Streams paths may include wildcards.  If a path is matched by more than
+    one config section, data from the last config section counts.
+
+    Decimated streams (paths containing '~decim-') are treated specially:
+      - They don't match wildcards
+      - When deleting data from a parent stream, data is also deleted
+        from its decimated streams, unless decimated=false
+
+    Rate is optional and is only used for the --estimate option.
+    """)
+    parser.add_argument("-u", "--url", action="store",
+                        default="http://localhost/nilmdb/",
+                        help="NilmDB server URL (default: %(default)s)")
+    parser.add_argument("-y", "--yes", action="store_true",
+                        default = False,
+                        help="Actually remove the data (default: no)")
+    parser.add_argument("-e", "--estimate", action="store_true",
+                        default = False,
+                        help="Estimate how much disk space will be used")
+    parser.add_argument("configfile", type=argparse.FileType('r'),
+                        help="Configuration file")
+    args = parser.parse_args(argv)
+
+    # Parse config file
+    config = ConfigParser.RawConfigParser()
+    config.readfp(args.configfile)
+
+    # List all streams
+    client = nilmdb.client.Client(args.url)
+    streamlist = client.stream_list(extended = True)
+
+    # Create config objects
+    streams = collections.OrderedDict()
+    for s in streamlist:
+        streams[s[0]] = StreamCleanupConfig(s)
+        m = re.search(r"^(.*)~decim-[0-9]+$", s[0])
+        if m:
+            streams[s[0]].decimated_from = m.group(1)
+
+    # Build up configuration
+    for section in config.sections():
+        matched = False
+        for path in streams.iterkeys():
+            # Decimated streams only allow exact matches
+            if streams[path].decimated_from and path != section:
+                continue
+            if not fnmatch.fnmatch(path, section):
+                continue
+            matched = True
+            options = config.options(section)
+
+            # Keep period (days, weeks, months, years)
+            if 'keep' in options:
+                streams[path].keep = TimePeriod(config.get(section, 'keep'))
+                options.remove('keep')
+
+            # Rate
+            if 'rate' in options:
+                streams[path].rate = config.getfloat(section, 'rate')
+                options.remove('rate')
+
+            # Decimated
+            if 'decimated' in options:
+                val = config.getboolean(section, 'decimated')
+                streams[path].clean_decimated = val
+                options.remove('decimated')
+
+            for leftover in options:
+                warn("option '%s' for '%s' is unknown", leftover, section)
+
+        if not matched:
+            warn("config for '%s' did not match any existing streams", section)
+
+    # List all decimated streams in the parent stream's info
+    for path in streams.keys():
+        src = streams[path].decimated_from
+        if src and src in streams:
+            if streams[src].clean_decimated:
+                streams[src].also_clean_paths.append(path)
+                del streams[path]
+
+    # Warn about streams that aren't getting cleaned up
+    for path in streams.keys():
+        if streams[path].keep is None or streams[path].keep.seconds() < 0:
+            warn("no config for existing stream '%s'", path)
+            del streams[path]
+
+    if args.estimate:
+        # Estimate disk usage
+        total = 0
+        for path in streams.keys():
+            rate = streams[path].rate
+            if not rate or rate < 0:
+                warn("unable to estimate disk usage for stream '%s' because "
+                     "the data rate is unknown", path)
+                continue
+            printf("%s:\n", path)
+            layout = streams[path].layout
+            dtype = nilmdb.client.numpyclient.layout_to_dtype(layout)
+            per_row = dtype.itemsize
+            per_sec = per_row * rate
+            printf("%17s: %s per row, %s rows per second\n",
+                   "base rate",
+                   human_size(per_row),
+                   round(rate,1))
+            printf("%17s: %s per hour, %s per day\n",
+                   "base size",
+                   human_size(per_sec * 3600),
+                   human_size(per_sec * 3600 * 24))
+
+            # If we'll be cleaning up decimated data, add an
+            # estimation for how much room decimated data takes up.
+            if streams[path].clean_decimated:
+                d_layout = "float32_" + str(3*(int(layout.split('_')[1])))
+                d_dtype = nilmdb.client.numpyclient.layout_to_dtype(d_layout)
+                # Assume the decimations will be a factor of 4
+                # sum_{k=0..inf} (rate / (n^k)) * d_dtype.itemsize
+                d_per_row = d_dtype.itemsize
+                factor = 4.0
+                d_per_sec = d_per_row * (rate / factor) * (1 / (1 - (1/factor)))
+                per_sec += d_per_sec
+                printf("%17s: %s per hour, %s per day\n",
+                       "with decimation",
+                       human_size(per_sec * 3600),
+                       human_size(per_sec * 3600 * 24))
+
+            keep = per_sec * streams[path].keep.seconds()
+            printf("%17s: %s\n\n",
+                   "keep " + str(streams[path].keep), human_size(keep))
+            total += keep
+        printf("Total estimated disk usage for these streams:\n")
+        printf("  %s\n", human_size(total))
+        raise SystemExit(0)
+
+    # Do the cleanup
+    for path in streams:
+        printf("%s: keep %s\n", path, streams[path].keep)
+
+        # Figure out the earliest timestamp we should keep.
+        intervals = [ Interval(start, end) for (start, end) in
+                      reversed(list(client.stream_intervals(path))) ]
+        total = 0
+        keep = seconds_to_timestamp(streams[path].keep.seconds())
+        for i in intervals:
+            total += i.end - i.start
+            if total <= keep:
+                continue
+            remove_before = i.start + (total - keep)
+            break
+        else:
+            printf("  nothing to do (only %s of data present)\n",
+                   streams[path].keep.describe_seconds(
+                       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(p, None, remove_before)
+
+    # All done
+    if not args.yes:
+        printf("Note: specify --yes to actually perform removals\n")
+    return
+
+if __name__ == "__main__":
+    main()

src/copy_one.py

@@ -5,6 +5,7 @@
 
 import nilmtools.filter
 import nilmdb.client
+from nilmdb.client.numpyclient import NumpyClient
 import numpy as np
 import sys
 
@@ -27,14 +28,14 @@ def main(argv = None):
     meta = f.client_src.stream_get_metadata(f.src.path)
     f.check_dest_metadata(meta)
 
-    # Copy all rows of data as ASCII strings
-    extractor = nilmdb.client.Client(f.src.url).stream_extract
-    inserter = nilmdb.client.Client(f.dest.url).stream_insert_context
+    # Copy all rows of data using the faster Numpy interfaces
+    extractor = NumpyClient(f.src.url).stream_extract_numpy
+    inserter = NumpyClient(f.dest.url).stream_insert_numpy_context
     for i in f.intervals():
         print "Processing", f.interval_string(i)
         with inserter(f.dest.path, i.start, i.end) as insert_ctx:
-            for row in extractor(f.src.path, i.start, i.end):
-                insert_ctx.insert(row + "\n")
+            for data in extractor(f.src.path, i.start, i.end):
+                insert_ctx.insert(data)
 
 if __name__ == "__main__":
     main()

src/decimate.py

@@ -71,7 +71,7 @@ def decimate(data, interval, args, insert_function, final):
     data = data[:n,:]
 
     # Reshape it into 3D so we can process 'factor' rows at a time
-    data.shape = (n // factor, factor, m)
+    data = data.reshape(n // factor, factor, m)
 
     # Fill the result
     out = np.c_[ np.mean(data[:,:,mean_col], axis=1),

src/decimate_auto.py

@@ -4,15 +4,19 @@ import nilmtools.filter
 import nilmtools.decimate
 import nilmdb.client
 import argparse
+import fnmatch
 
 def main(argv = None):
     parser = argparse.ArgumentParser(
         formatter_class = argparse.RawDescriptionHelpFormatter,
-        version = "1.0",
+        version = nilmtools.__version__,
         description = """\
     Automatically create multiple decimations from a single source
     stream, continuing until the last decimated level contains fewer
     than 500 points total.
+
+    Wildcards and multiple paths are accepted.  Decimated paths are
+    ignored when matching wildcards.
     """)
     parser.add_argument("-u", "--url", action="store",
                         default="http://localhost/nilmdb/",
@@ -23,20 +27,36 @@ def main(argv = None):
                         default = False,
                         help="Force metadata changes if the dest "
                         "doesn't match")
-    parser.add_argument("path", action="store",
+    parser.add_argument("path", action="store", nargs='+',
                         help='Path of base stream')
     args = parser.parse_args(argv)
 
     # Pull out info about the base stream
     client = nilmdb.client.Client(args.url)
 
-    info = nilmtools.filter.get_stream_info(client, args.path)
-    if not info:
-        raise Exception("path " + args.path + " not found")
+    # Find list of paths to process
+    streams = [ unicode(s[0]) for s in client.stream_list() ]
+    streams = [ s for s in streams if "~decim-" not in s ]
+    paths = []
+    for path in args.path:
+        new = fnmatch.filter(streams, unicode(path))
+        if not new:
+            print "error: no stream matched path:", path
+            raise SystemExit(1)
+        paths.extend(new)
 
-    meta = client.stream_get_metadata(args.path)
+    for path in paths:
+        do_decimation(client, args, path)
+
+def do_decimation(client, args, path):
+    print "Decimating", path
+    info = nilmtools.filter.get_stream_info(client, path)
+    if not info:
+        raise Exception("path " + path + " not found")
+
+    meta = client.stream_get_metadata(path)
     if "decimate_source" in meta:
-        print "Stream", args.path, "was decimated from", meta["decimate_source"]
+        print "Stream", path, "was decimated from", meta["decimate_source"]
         print "You need to pass the base stream instead"
         raise SystemExit(1)
 
@@ -53,7 +73,7 @@ def main(argv = None):
         if info.rows <= 500:
             break
         factor *= args.factor
-        new_path = "%s~decim-%d" % (args.path, factor)
+        new_path = "%s~decim-%d" % (path, factor)
 
         # Create the stream if needed
         new_info = nilmtools.filter.get_stream_info(client, new_path)
@@ -72,5 +92,7 @@ def main(argv = None):
         # Update info using the newly decimated stream
         info = nilmtools.filter.get_stream_info(client, new_path)
 
+    return
+
 if __name__ == "__main__":
     main()

src/filter.py

@@ -4,6 +4,7 @@ from __future__ import absolute_import
 
 import nilmdb.client
 from nilmdb.client import Client
+from nilmdb.client.numpyclient import NumpyClient
 from nilmdb.utils.printf import *
 from nilmdb.utils.time import (parse_time, timestamp_to_human,
                                timestamp_to_seconds)
@@ -66,7 +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
@@ -77,6 +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):
@@ -232,8 +236,14 @@ class Filter(object):
         metadata = self._client_dest.stream_get_metadata(self.dest.path)
         if not self.force_metadata:
             for key in data:
-                wanted = str(data[key])
+                wanted = data[key]
+                if not isinstance(wanted, basestring):
+                    wanted = str(wanted)
                 val = metadata.get(key, wanted)
+                # Force UTF-8 encoding for comparison and display
+                wanted = wanted.encode('utf-8')
+                val = val.encode('utf-8')
+                key = key.encode('utf-8')
                 if val != wanted and self.dest.rows > 0:
                     m =  "Metadata in destination stream:\n"
                     m += "  %s = %s\n" % (key, val)
@@ -247,72 +257,7 @@ class Filter(object):
         # All good -- write the metadata in case it's not already there
         self._client_dest.stream_update_metadata(self.dest.path, data)
 
-    # Main processing helper
-    def process_python(self, function, rows, args = None, partial = False):
-        """Process data in chunks of 'rows' data at a time.
-
-        This provides data as nested Python lists and expects the same
-        back.
-
-        function: function to process the data
-        rows: maximum number of rows to pass to 'function' at once
-        args: tuple containing extra arguments to pass to 'function'
-        partial: if true, less than 'rows' may be passed to 'function'.
-                 if false, partial data at the end of an interval will
-                 be dropped.
-
-        'function' should be defined like:
-            function(data, *args)
-        It will be passed a list containing up to 'rows' rows of
-        data from the source stream, and any arguments passed in
-        'args'.  It should transform the data as desired, and return a
-        new list of rdata, which will be inserted into the destination
-        stream.
-        """
-        if args is None:
-            args = []
-        extractor = Client(self.src.url).stream_extract
-        inserter = Client(self.dest.url).stream_insert_context
-
-        # Parse input data.  We use homogenous types for now, which
-        # means the timestamp type will be either float or int.
-        if "int" in self.src.layout_type:
-            parser = lambda line: [ int(x) for x in line.split() ]
-        else:
-            parser = lambda line: [ float(x) for x in line.split() ]
-
-        # Format output data.
-        formatter = lambda row: " ".join([repr(x) for x in row]) + "\n"
-
-        for interval in self.intervals():
-            print "Processing", self.interval_string(interval)
-            with inserter(self.dest.path,
-                          interval.start, interval.end) as insert_ctx:
-                src_array = []
-                for line in extractor(self.src.path,
-                                      interval.start, interval.end):
-                    # Read in data
-                    src_array.append([ float(x) for x in line.split() ])
-
-                    if len(src_array) == rows:
-                        # Pass through filter function
-                        dest_array = function(src_array, *args)
-
-                        # Write result to destination
-                        out = [ formatter(row) for row in dest_array ]
-                        insert_ctx.insert("".join(out))
-
-                        # Clear source array
-                        src_array = []
-
-                # Take care of partial chunk
-                if len(src_array) and partial:
-                    dest_array = function(src_array, *args)
-                    out = [ formatter(row) for row in dest_array ]
-                    insert_ctx.insert("".join(out))
-
-    # Like process_python, but provides Numpy arrays and allows for
-    # partial processing.
+    # The main filter processing method.
     def process_numpy(self, function, args = None, rows = 100000):
         """For all intervals that exist in self.src but don't exist in
         self.dest, call 'function' with a Numpy array corresponding to
@@ -339,40 +284,26 @@ 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 = []
-        extractor = Client(self.src.url).stream_extract
-        inserter = Client(self.dest.url).stream_insert_context
-
-        # Format output data.
-        formatter = lambda row: " ".join([repr(x) for x in row]) + "\n"
-
-        def batch(iterable, size):
-            c = itertools.count()
-            for k, g in itertools.groupby(iterable, lambda x: c.next() // size):
-                yield g
+        extractor = NumpyClient(self.src.url).stream_extract_numpy
+        inserter = NumpyClient(self.dest.url).stream_insert_numpy_context
 
         for interval in self.intervals():
             print "Processing", self.interval_string(interval)
             with inserter(self.dest.path,
                           interval.start, interval.end) as insert_ctx:
-                def insert_function(array):
-                    s = cStringIO.StringIO()
-                    if len(np.shape(array)) != 2:
-                        raise Exception("array must be 2-dimensional")
-                    np.savetxt(s, array)
-                    insert_ctx.insert(s.getvalue())
-
-                extract = extractor(self.src.path, interval.start, interval.end)
+                insert_function = insert_ctx.insert
                 old_array = np.array([])
-                for batched in batch(extract, rows):
-                    # Read in this batch of data.  This turns out to
-                    # be a very fast way to read and convert it (order
-                    # of magnitude faster than numpy.loadtxt)
-                    new_array = np.fromstring("\n".join(batched), sep=' ')
-                    new_array = new_array.reshape(-1, self.src.total_count)
-
+                for new_array in extractor(self.src.path,
+                                           interval.start, interval.end,
+                                           layout = self.src.layout,
+                                           maxrows = rows):
                     # If we still had old data left, combine it
                     if old_array.shape[0] != 0:
                         array = np.vstack((old_array, new_array))
@@ -401,7 +332,13 @@ 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/median.py

@@ -0,0 +1,43 @@
+#!/usr/bin/python
+import nilmtools.filter, scipy.signal
+
+def main(argv = None):
+    f = nilmtools.filter.Filter()
+    parser = f.setup_parser("Median Filter")
+    group = parser.add_argument_group("Median filter options")
+    group.add_argument("-z", "--size", action="store", type=int, default=25,
+                       help = "median filter size (default %(default)s)")
+    group.add_argument("-d", "--difference", action="store_true",
+                       help = "store difference rather than filtered values")
+
+    try:
+        args = f.parse_args(argv)
+    except nilmtools.filter.MissingDestination as e:
+        print "Source is %s (%s)" % (e.src.path, e.src.layout)
+        print "Destination %s doesn't exist" % (e.dest.path)
+        print "You could make it with a command like:"
+        print "  nilmtool -u %s create %s %s" % (e.dest.url,
+                                                 e.dest.path, e.src.layout)
+        raise SystemExit(1)
+
+    meta = f.client_src.stream_get_metadata(f.src.path)
+    f.check_dest_metadata({ "median_filter_source": f.src.path,
+                            "median_filter_size": args.size,
+                            "median_filter_difference": repr(args.difference) })
+
+    f.process_numpy(median_filter, args = (args.size, args.difference))
+
+def median_filter(data, interval, args, insert, final):
+    (size, diff) = args
+    (rows, cols) = data.shape
+    for i in range(cols - 1):
+        filtered = scipy.signal.medfilt(data[:, i+1], size)
+        if diff:
+            data[:, i+1] -= filtered
+        else:
+            data[:, i+1] = filtered
+    insert(data)
+    return rows
+
+if __name__ == "__main__":
+    main()

src/prep.py

@@ -3,12 +3,14 @@
 # Spectral envelope preprocessor.
 # Requires two streams as input: the original raw data, and sinefit data.
 
+from nilmdb.utils.printf import *
+from nilmdb.utils.time import timestamp_to_human
 import nilmtools.filter
 import nilmdb.client
 from numpy import *
 import scipy.fftpack
 import scipy.signal
-from matplotlib import pyplot as p
+#from matplotlib import pyplot as p
 import bisect
 
 def main(argv = None):
@@ -19,12 +21,14 @@ def main(argv = None):
     group.add_argument("-c", "--column", action="store", type=int,
                        help="Column number (first data column is 1)")
     group.add_argument("-n", "--nharm", action="store", type=int, default=4,
-                       help="number of odd harmonics to compute")
+                       help="number of odd harmonics to compute (default 4)")
+    group.add_argument("-N", "--nshift", action="store", type=int, default=1,
+                       help="number of shifted FFTs per period (default 1)")
     exc = group.add_mutually_exclusive_group()
     exc.add_argument("-r", "--rotate", action="store", type=float,
-                     help="rotate FFT output by this many degrees")
+                     help="rotate FFT output by this many degrees (default 0)")
     exc.add_argument("-R", "--rotate-rad", action="store", type=float,
-                     help="rotate FFT output by this many radians")
+                     help="rotate FFT output by this many radians (default 0)")
 
     group.add_argument("srcpath", action="store",
                        help="Path of raw input, e.g. /foo/raw")
@@ -44,6 +48,10 @@ def main(argv = None):
         print "  nilmtool -u %s create %s %s" % (e.dest.url, e.dest.path, rec)
         raise SystemExit(1)
 
+    if f.dest.layout_count != args.nharm * 2:
+        print "error: need", args.nharm*2, "columns in destination stream"
+        raise SystemExit(1)
+
     # Check arguments
     if args.column is None or args.column < 1:
         parser.error("need a column number >= 1")
@@ -51,6 +59,9 @@ def main(argv = None):
     if args.nharm < 1 or args.nharm > 32:
         parser.error("number of odd harmonics must be 1-32")
 
+    if args.nshift < 1:
+        parser.error("number of shifted FFTs must be >= 1")
+
     if args.rotate is not None:
         rotation = args.rotate * 2.0 * pi / 360.0
     else:
@@ -68,58 +79,100 @@ def main(argv = None):
     # Check and set metadata in prep stream
     f.check_dest_metadata({ "prep_raw_source": f.src.path,
                             "prep_sinefit_source": sinefit.path,
-                            "prep_column": args.column })
+                            "prep_column": args.column,
+                            "prep_rotation": repr(rotation) })
 
     # Run the processing function on all data
     f.process_numpy(process, args = (client_sinefit, sinefit.path, args.column,
-                                     args.nharm, rotation))
+                                     args.nharm, rotation, args.nshift))
 
 def process(data, interval, args, insert_function, final):
-    (client, sinefit_path, column, nharm, rotation) = args
+    (client, sinefit_path, column, nharm, rotation, nshift) = args
     rows = data.shape[0]
     data_timestamps = data[:,0]
 
+    if rows < 2:
+        return 0
+
+    last_inserted = [nilmdb.utils.time.min_timestamp]
+    def insert_if_nonoverlapping(data):
+        """Call insert_function to insert data, but only if this
+        data doesn't overlap with other data that we inserted."""
+        if data[0][0] <= last_inserted[0]:
+            return
+        last_inserted[0] = data[-1][0]
+        insert_function(data)
+
     processed = 0
     out = zeros((1, nharm * 2 + 1))
     # Pull out sinefit data for the entire time range of this block
     for sinefit_line in client.stream_extract(sinefit_path,
                                               data[0, 0], data[rows-1, 0]):
-        # Extract sinefit data to get zero crossing timestamps
+        def prep_period(t_min, t_max, rot):
+            """
+            Compute prep coefficients from time t_min to t_max, which
+            are the timestamps of the start and end of one period.
+            Results are rotated by an additional extra_rot before
+            being inserted into the database.  Returns the maximum
+            index processed, or None if the period couldn't be
+            processed.
+            """
+            # Find the indices of data that correspond to (t_min, t_max)
+            idx_min = bisect.bisect_left(data_timestamps, t_min)
+            idx_max = bisect.bisect_left(data_timestamps, t_max)
+            if idx_min >= idx_max or idx_max >= len(data_timestamps):
+                return None
+
+            # Perform FFT over those indices
+            N = idx_max - idx_min
+            d = data[idx_min:idx_max, column]
+            F = scipy.fftpack.fft(d) * 2.0 / N
+
+            # If we wanted more harmonics than the FFT gave us, pad with zeros
+            if N < (nharm * 2):
+                F = r_[F, zeros(nharm * 2 - N)]
+
+            # Fill output data.
+            out[0, 0] = round(t_min)
+            for k in range(nharm):
+                Fk = F[2 * k + 1] * e**(rot * 1j * (k+1))
+                out[0, 2 * k + 1] = -imag(Fk) # Pk
+                out[0, 2 * k + 2] = real(Fk)  # Qk
+
+            insert_if_nonoverlapping(out)
+            return idx_max
+
+        # Extract sinefit data to get zero crossing timestamps.
+        # t_min = beginning of period
+        # t_max = end of period
         (t_min, f0, A, C) = [ float(x) for x in sinefit_line.split() ]
         t_max = t_min + 1e6 / f0
 
-        # Find the indices of data that correspond to (t_min, t_max)
-        idx_min = bisect.bisect_left(data_timestamps, t_min)
-        idx_max = bisect.bisect_left(data_timestamps, t_max)
-        if idx_min >= idx_max:
-            # something's wonky; ignore this period
-            continue
-        if idx_max >= len(data_timestamps):
-            # max is likely past the end of our chunk, so stop
-            # processing this chunk now.
-            break
+        # Compute prep over shifted windows of the period
+        # (nshift is typically 1)
+        for n in range(nshift):
+            # Compute timestamps and rotations for shifted window
+            time_shift = n * (t_max - t_min) / nshift
+            shifted_min = t_min + time_shift
+            shifted_max = t_max + time_shift
+            angle_shift = n * 2 * pi / nshift
+            shifted_rot = rotation - angle_shift
 
-        # Perform FFT over those indices
-        N = idx_max - idx_min
-        d = data[idx_min:idx_max, column]
-        F = scipy.fftpack.fft(d) / N
+            # Run prep computation
+            idx_max = prep_period(shifted_min, shifted_max, shifted_rot)
+            if not idx_max:
+                break
+            processed = idx_max
 
-        # If we wanted more harmonics than we have, pad with zeros
-        if N < (nharm * 2):
-            F = r_[F, zeros(nharm * 2 - N)]
-
-        # Fill output data
-        out[0, 0] = t_min
-        for k in range(nharm):
-            Fk = F[2 * k + 1] * e**(rotation * 1j * (k+1))
-            out[0, 2 * k + 1] = -imag(Fk) # Pk
-            out[0, 2 * k + 2] = real(Fk)  # Qk
-
-        # Insert it and continue
-        insert_function(out)
-        processed = idx_max
-
-    print "Processed", processed, "of", rows, "rows"
+    # If we processed no data but there's lots in here, pretend we
+    # processed half of it.
+    if processed == 0 and rows > 10000:
+        processed = rows / 2
+        printf("%s: warning: no periods found; skipping %d rows\n",
+               timestamp_to_human(data[0][0]), processed)
+    else:
+        printf("%s: processed %d of %d rows\n",
+               timestamp_to_human(data[0][0]), processed, rows)
     return processed
 
 if __name__ == "__main__":

src/sinefit.py

@@ -18,6 +18,15 @@ def main(argv = None):
     group.add_argument('-f', '--frequency', action='store', type=float,
                        default=60.0,
                        help='Approximate frequency (default: %(default)s)')
+    group.add_argument('-m', '--min-freq', action='store', type=float,
+                       help='Minimum valid frequency '
+                       '(default: approximate frequency / 2))')
+    group.add_argument('-M', '--max-freq', action='store', type=float,
+                       help='Maximum valid frequency '
+                       '(default: approximate frequency * 2))')
+    group.add_argument('-a', '--min-amp', action='store', type=float,
+                       default=20.0,
+                       help='Minimum signal amplitude (default: %(default)s)')
 
     # Parse arguments
     try:
@@ -34,13 +43,24 @@ def main(argv = None):
         parser.error("need a column number >= 1")
     if args.frequency < 0.1:
         parser.error("frequency must be >= 0.1")
+    if args.min_freq is None:
+        args.min_freq = args.frequency / 2
+    if args.max_freq is None:
+        args.max_freq = args.frequency * 2
+    if (args.min_freq > args.max_freq or
+        args.min_freq > args.frequency or
+        args.max_freq < args.frequency):
+        parser.error("invalid min or max frequency")
+    if args.min_amp < 0:
+        parser.error("min amplitude must be >= 0")
 
     f.check_dest_metadata({ "sinefit_source": f.src.path,
                             "sinefit_column": args.column })
-    f.process_numpy(process, args = (args.column, args.frequency))
+    f.process_numpy(process, args = (args.column, args.frequency, args.min_amp,
+                                     args.min_freq, args.max_freq))
 
 def process(data, interval, args, insert_function, final):
-    (column, f_expected) = args
+    (column, f_expected, a_min, f_min, f_max) = args
     rows = data.shape[0]
 
     # Estimate sampling frequency from timestamps
@@ -66,18 +86,24 @@ def process(data, interval, args, insert_function, final):
         (A, f0, phi, C) = sfit4(this, fs)
 
         # Check bounds.  If frequency is too crazy, ignore this window
-        if f0 < (f_expected/2) or f0 > (f_expected*2):
-            print "frequency", f0, "too far from expected value", f_expected
+        if f0 < f_min or f0 > f_max:
+            print "frequency", f0, "outside valid range", f_min, "-", f_max
+            start += N
+            continue
+
+        # If amplitude is too low, results are probably just noise
+        if A < a_min:
+            print "amplitude", A, "below minimum threshold", a_min
             start += N
             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)
-        zc_n = (3 * pi / 2 - phi) / (f0 / fs * 2 * pi)
+        #     n = (0 - phi) / (f0/fs * 2 * pi)
+        zc_n = (0 - phi) / (f0 / fs * 2 * pi)
         period_n = fs/f0
 
         # Add periods to make N positive
@@ -123,15 +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)
@@ -156,32 +182,31 @@ 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
-    # first guess for A0, B0 using 3-parameter fit (step c)
-    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)
-    for idx in range(6):
-        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
-        w = w + s[3]	# update frequency estimate
-
-    ## Extract results
-    A = sqrt(s[0]*s[0] + s[1]*s[1]) # eqn B.21
-    f0 = w / (2*pi)
+    # Fit it.  We'll catch exceptions here and just returns zeros
+    # if something fails with the least squares fit, etc.
     try:
-        phi = -arctan2(s[1], s[0]) # eqn B.22
-    except TypeError:
+        # first guess for A0, B0 using 3-parameter fit (step c)
+        s = zeros(3)
+        w = 2*pi*f0
+
+        # Now iterate 7 times (step b, plus 6 iterations of step i)
+        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
+            w = w + s[3]	# update frequency estimate
+
+        ## Extract results
+        A = sqrt(s[0]*s[0] + s[1]*s[1]) # eqn B.21
+        f0 = w / (2*pi)
+        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:
         # something broke down, just return zeros
         return (0, 0, 0, 0)
-    C = s[2]
-
-    return (A, f0, phi, C)
 
 if __name__ == "__main__":
     main()