Add Curve loading to hooke.playlist.Playlist.

Highlights:
  * NotRecognized.__get/setstate__ for Pickling through the Queues.
    Perhaps this would be better solved in Failure.__get/setstate__?
    The current fix works for the moment though.
  * Use Curve.data == None to indicate unloaded curves.
  * Fix TutorialDriver.is_me(self) -> is_me(self, path)
  * Added ._load* to Playlist, so it only caches ._max_loaded curves
    in memory.
  * Fix broken Playlist.from_string doctest.

diff --git a/hooke/curve.py b/hooke/curve.py
index 816a921a86470f842ee2bda1d7d2131a73722de0..216722dc8d849cac3ccfdf8b2de29963c08b32af 100644 (file)
--- a/hooke/curve.py
+++ b/hooke/curve.py
@@ -26,9 +26,16 @@ import numpy
 
 class NotRecognized (ValueError):
     def __init__(self, curve):
-        msg = 'Not a recognizable curve format: %s' % curve.path
-        ValueError.__init__(self, msg)
-        self.curve = curve
+        self.__setstate__(curve)
+
+    def __getstate__(self):
+        return self.curve
+
+    def __setstate__(self, data):
+        if isinstance(data, Curve):
+            msg = 'Not a recognizable curve format: %s' % data.path
+            super(NotRecognized, self).__init__(msg)
+            self.curve = data
 
 class Data (numpy.ndarray):
     """Stores a single, continuous data set.
@@ -87,7 +94,7 @@ class Curve (object):
         #the data dictionary contains: {name of data: list of data sets [{[x], [y]}]
         self.path = path
         self.driver = None
-        self.data = []
+        self.data = None
         if info == None:
             info = {}
         self.info = info
@@ -106,4 +113,12 @@ class Curve (object):
     def load(self):
         """Use the driver to read the curve into memory.
         """
-        pass
+        data,info = self.driver.read(self.path)
+        self.data = data
+        for key,value in info.items():
+            self.info[key] = value
+
+    def unload(self):
+        """Release memory intensive :attr:`.data`.
+        """
+        self.data = None

diff --git a/hooke/driver/__init__.py b/hooke/driver/__init__.py
index 92ae9729a81447f560f0983b70b6587de81edae1..b6324cb3370f4d92f197b42e1345d10d7a1c4796 100644 (file)
--- a/hooke/driver/__init__.py
+++ b/hooke/driver/__init__.py
@@ -81,7 +81,7 @@ class Driver(object):
 
     def read(self, path):
         """Read data from `path` and return a
-        (:class:`hooke.curve.Data`, `info`) tuple.
+        ([:class:`hooke.curve.Data`, ...], `info`) tuple.
 
         The `info` :class:`dict` must contain values for the keys:
         'filetype' and 'experiment'.  See :class:`hooke.curve.Curve`

diff --git a/hooke/driver/tutorial.py b/hooke/driver/tutorial.py
index d68393ead1cb9a7ded7e06367d13a94637e0cf76..4553369f6cb546ded76ba249dd218ff3b3c3f758 100644 (file)
--- a/hooke/driver/tutorial.py
+++ b/hooke/driver/tutorial.py
@@ -93,7 +93,7 @@ class TutorialDriver (Driver):
                     help='Set the units used for the x data.'),
             ]
 
-    def is_me(self):
+    def is_me(self, path):
         """YOU MUST OVERRIDE Driver.is_me.
 
         RETURNS: Boolean (`True` or `False`)
@@ -106,7 +106,7 @@ class TutorialDriver (Driver):
         automatically.
         """
 
-        f = open(self.filename, 'r')
+        f = open(path, 'r')
         header = f.readline() # we only need the first line
         f.close()
 

diff --git a/hooke/playlist.py b/hooke/playlist.py
index 4cc897aa8272d23dfaccfe2847c47a48257d99b4..ca38b4e923936c77ff57f807564613a75cae0979 100644 (file)
--- a/hooke/playlist.py
+++ b/hooke/playlist.py
@@ -81,10 +81,12 @@ class Playlist (NoteIndexList):
     def __init__(self, drivers, name=None):
         super(Playlist, self).__init__(name=name)
         self.drivers = drivers
+        self._loaded = [] # List of loaded curves, see :meth:`._load`.
+        self._max_loaded = 100 # curves to hold in memory simultaneously.
 
     def append_curve_by_path(self, path, info=None, identify=True):
         if self.path != None:
-            path = os.path.join(self.path, path)
+            path = os.path.join(os.path.dirname(self.path), path)
         path = os.path.normpath(path)
         c = curve.Curve(path, info=info)
         if identify == True:
@@ -92,6 +94,24 @@ class Playlist (NoteIndexList):
         self.append(c)
         return c
 
+    def current(self):
+        curve = super(Playlist, self).current()
+        self._load(curve)
+        return curve
+
+    def _load(self, curve):
+        if curve != None and curve not in self._loaded:
+            if curve not in self:
+                self.append(curve)
+            if curve.driver == None:
+                c.identify(self.drivers)
+            if curve.data == None:
+                curve.load()
+            self._loaded.append(curve)
+            if len(self._loaded) > self._max_loaded:
+                oldest = self._loaded.pop(0)
+                oldest.unload()
+
 class FilePlaylist (Playlist):
     version = '0.1'
 
@@ -199,7 +219,7 @@ class FilePlaylist (Playlist):
         root.unlink() # break circular references for garbage collection
         return string
 
-    def _from_xml_doc(self, doc):
+    def _from_xml_doc(self, doc, identify=True):
         """Load a playlist from an :class:`xml.dom.minidom.Document`
         instance.
         """
@@ -217,10 +237,10 @@ class FilePlaylist (Playlist):
             path = curve_element.getAttribute('path')
             info = dict(curve_element.attributes.items())
             info.pop('path')
-            self.append_curve_by_path(path, info, identify=False)
+            self.append_curve_by_path(path, info, identify=identify)
         self.jump(self._index) # ensure valid index
 
-    def from_string(self, string):
+    def from_string(self, string, identify=True):
         """Load a playlist from a string.
 
         Examples
@@ -233,8 +253,8 @@ class FilePlaylist (Playlist):
         ... </playlist>
         ... '''
         >>> p = FilePlaylist(drivers=[],
-        ...                  path=os.path.join('path', 'to','playlist'))
-        >>> p.from_string(string)
+        ...                  path=os.path.join('path', 'to', 'my', 'playlist'))
+        >>> p.from_string(string, identify=False)
         >>> p._index
         1
         >>> p.info
@@ -245,14 +265,14 @@ class FilePlaylist (Playlist):
         path/to/curve/two
         """
         doc = xml.dom.minidom.parseString(string)
-        self._from_xml_doc(doc)
+        self._from_xml_doc(doc, identify=identify)
 
-    def load(self, path=None):
+    def load(self, path=None, identify=True):
         """Load a playlist from a file.
         """
         self.set_path(path)
         doc = xml.dom.minidom.parse(self.path)
-        self._from_xml_doc(doc)
+        self._from_xml_doc(doc, identify=identify)
         self._digest = self.digest()
 
     def save(self, path=None):