Added a new fromiter() constructor. Can use a Fixed shape or TypeVar …

…(unknown length).

blaze/__init__.py

@@ -14,7 +14,7 @@
 dtype   = dshape
 
 from params import params
-from toplevel import open, zeros, ones
+from toplevel import open, zeros, ones, fromiter
 
 # Shorthand namespace dump
 from datashape.shorthand import *

blaze/carray/__init__.py

@@ -11,7 +11,7 @@
     # _cparams as cparams,
     # blosc_version, _blosc_set_nthreads as blosc_set_nthreads
     )
-from toplevel import cparams, open, zeros, ones
+from toplevel import cparams, open, zeros, ones, fromiter
 from version import __version__
 
 # doesn't work for reasons I don't understand

blaze/carray/toplevel.py

@@ -161,16 +161,14 @@ def fromiter(iterable, dtype, count, **kwargs):
     dtype = np.dtype(dtype)
     if dtype.kind == "V":
         # A ctable
-        obj = ca.ctable(np.array([], dtype=dtype),
-                        expectedlen=expectedlen,
-                        **kwargs)
+        obj = ctable(np.array([], dtype=dtype),
+                     expectedlen=expectedlen, **kwargs)
         chunklen = sum(obj.cols[name].chunklen
                        for name in obj.names) // len(obj.names)
     else:
         # A carray
-        obj = ca.carray(np.array([], dtype=dtype),
-                        expectedlen=expectedlen,
-                        **kwargs)
+        obj = carray(np.array([], dtype=dtype),
+                     expectedlen=expectedlen, **kwargs)
         chunklen = obj.chunklen
 
     # Then fill it

blaze/tests/test_quickstart.py

@@ -22,6 +22,16 @@ def test_simple_persistence():
     # Remove everything under the temporary dir
     shutil.rmtree(td)
 
+def test_ones():
+    from blaze import ones
+
+    a = ones('10, float64', params=params(clevel=5))
+
+def test_fromiter():
+    from blaze import fromiter
+
+    a = fromiter(xrange(10), 'x, float64', params=params(clevel=5))
+
 def test_custom_dshape():
     from blaze import Array, RecordDecl
     from blaze import int32, string

blaze/toplevel.py

@@ -7,7 +7,7 @@
 from sources.chunked import CArraySource
 
 from table import NDArray, Array
-from blaze.datashape.coretypes import from_numpy, to_numpy
+from blaze.datashape.coretypes import from_numpy, to_numpy, TypeVar, Fixed
 from blaze import carray, dshape as _dshape
 
 import numpy as np
@@ -71,6 +71,34 @@ def ones(dshape, params=None):
                               params=params)
         return Array(source)
 
+def fromiter(iterable, dshape, params=None):
+    """ Create an Array and fill it with values from `iterable`.
+    """
+    if isinstance(dshape, basestring):
+        dshape = _dshape(dshape)
+    shape, dtype = dshape.parameters[:-1], dshape.parameters[-1]
+    # Check the shape part
+    if len(shape) > 1:
+        raise ValueError("shape can be only 1-dimensional")
+    length = shape[0]
+    count = -1
+    if type(length) == TypeVar:
+        count = -1
+    elif type(length) == Fixed:
+        count = length.val
+
+    dtype = dtype.to_dtype()
+    # Now, create the Array itself (using the carray backend)
+    cparams, rootdir, format_flavor = to_cparams(params or _params())
+    if rootdir is not None:
+        carray.fromiter(iterable, dtype, count=count,
+                        rootdir=rootdir, cparams=cparams)
+        return open(rootdir)
+    else:
+        ica = carray.fromiter(iterable, dtype, count=count, cparams=cparams)
+        source = CArraySource(ica, params=params)
+        return Array(source)
+
 def loadtxt(filetxt, storage):
     """ Convert txt file into Blaze native format """
     Array(np.loadtxt(filetxt), params=params(storage=storage))