strarray

Author: RamanjaneyuluIdavalapati

.travis.yml

@@ -9,8 +9,8 @@ deploy:
 - provider: releases
   api_key:
     secure: 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
-  name: diskarray-0.1.6
-  tag_name: 0.1.6
+  name: diskarray-0.1.7
+  tag_name: 0.1.7
   on:
     repo: deep-compute/diskarray
 - provider: pypi

diskarray/__init__.py

@@ -1,3 +1,4 @@
 from .command import main
 from .diskarray import DiskArray
 from .vararray import DiskVarArray
+from .strarray import DiskStringArray

diskarray/diskarray.py

@@ -8,6 +8,22 @@
 from .exception import AppendNotSupported
 
 class DiskArray(object):
+    '''
+    Stores binary data on disk as a memory mapped file
+    using numpy.memmap. Allows for growing the disk data
+    by appending and extending.
+
+    Links:
+    * https://en.wikipedia.org/wiki/Memory-mapped_file
+
+    # FIXME:
+    1. Explain capacity and actual shape
+    2. Explain growby
+    3. Explain not having to specify shape for 1d arrays
+    4. Explain using structured arrays
+    5. Why memory mapping? What does it provide?
+    6. Why not use np.save and np.load?
+    '''
     GROWBY = 10000
 
     def __init__(self, fpath, dtype, mode='r+', shape=None,
@@ -69,10 +85,13 @@ def _shape_bytes(self, shape, dtype_bytes):
 
     def _truncate_if_needed(self):
         fd = os.open(self._fpath, os.O_RDWR|os.O_CREAT)
-        dtype_bytes = np.dtype(self._dtype).itemsize
-        nbytes = self._shape_bytes(self._shape, dtype_bytes)
-        os.ftruncate(fd, nbytes)
-        self._capacity_shape = self._shape
+        try:
+            dtype_bytes = np.dtype(self._dtype).itemsize
+            nbytes = self._shape_bytes(self._shape, dtype_bytes)
+            os.ftruncate(fd, nbytes)
+            self._capacity_shape = self._shape
+        finally:
+            os.close(fd)
         self._create_ndarray()
 
     @property
@@ -184,6 +203,11 @@ def grow(self, n):
         # FIXME: code
         pass
 
+    def close(self):
+        self.data._mmap.close()
+        del self.data
+        del self._fpath
+
     def truncate(self, n):
         # FIXME: code
         pass

diskarray/strarray.py

@@ -0,0 +1,26 @@
+from logging import Logger
+
+import numpy as np
+
+from .vararray import DiskVarArray
+
+class DiskStringArray(DiskVarArray):
+    # Index to word
+    def __init__(self, dpath, mode='r+',
+            growby=DiskVarArray.GROWBY,
+            log=Logger):
+        super(DiskStringArray, self).__init__(dpath,
+                dtype=np.uint8, dtype_index=np.uint64,
+                mode=mode, growby=growby, log=log)
+
+    def __getitem__(self, idx):
+        data = super(DiskStringArray, self).__getitem__(idx)
+        return data.tostring()
+
+    def append(self, v):
+        v = np.array(list(v), dtype=np.uint8)
+        return super(DiskStringArray, self).append(v)
+
+    def extend(self, v):
+        v = [np.array(list(x), dtype=np.uint8) for x in v]
+        return super(DiskStringArray, self).extend(v)

diskarray/vararray.py

@@ -109,6 +109,9 @@ def num_lists(self):
         '''
         return len(self.index)
 
+    def __len__(self):
+        return self.num_lists
+
     def append(self, v):
         '''
         >>> d = DiskVarArray('/tmp/test3', dtype='uint32')
@@ -124,10 +127,12 @@ def append(self, v):
         self.data.extend(v)
 
     def extend(self, v):
-        # FIXME: assert v properties
-        # FIXME: can we avoid the for loop for perf?
-        for index in enumerate(v):
-            self.append(v[index])
+        lengths = np.cumsum([len(x) for x in v])
+        self.index.append(0)
+        self.index.extend(lengths[:-1])
+
+        vals = np.concatenate(v)
+        self.data.extend(vals)
 
     def destroy(self):
         '''
@@ -144,3 +149,7 @@ def destroy(self):
 
         self.index.destroy()
         self.index = None
+
+    def close(self):
+        self.data.close()
+        self.index.close()

setup.py

@@ -1,6 +1,6 @@
 from setuptools import setup, find_packages
 
-version = '0.1.6'
+version = '0.1.7'
 setup(
     name="diskarray",
     version=version,