[Numpy-discussion] ANN: BLZ 0.6.1 has been released

2014-01-25 Thread Francesc Alted
Announcing BLZ 0.6 series = What it is -- BLZ is a chunked container for numerical data. Chunking allows for efficient enlarging/shrinking of data container. In addition, it can also be compressed for reducing memory/disk needs. The compression process is carrie

[Numpy-discussion] ANN: python-blosc 1.2.0 released

2014-01-25 Thread Francesc Alted
= Announcing python-blosc 1.2.0 = What is new? This release adds support for the multiple compressors added in Blosc 1.3 series. The new compressors are: * lz4 (http://code.google.com/p/lz4/): A very fast compressor/decompr

[Numpy-discussion] ANN: numexpr 2.3 (final) released

2014-01-25 Thread Francesc Alted
== Announcing Numexpr 2.3 == Numexpr is a fast numerical expression evaluator for NumPy. With it, expressions that operate on arrays (like "3*a+4*b") are accelerated and use less memory than doing the same calculation in Python. It wears multi-th

Re: [Numpy-discussion] Text array dtype for numpy

2014-01-25 Thread Oscar Benjamin
On 24 January 2014 22:43, Chris Barker wrote: > Oscar, > > Cool stuff, thanks! > > I'm wondering though what the use-case really is. The use-case is precisely the use-case for dtype='S' on Py2 except that it also works on Py3. > The P3 text model > (actually the py2 one, too), is quite clear th

Re: [Numpy-discussion] Comparison changes

2014-01-25 Thread Stéfan van der Walt
On Sat, 25 Jan 2014 01:05:15 +0100, Sebastian Berg wrote: > 1. Comparison with None will broadcast in the future, so that `arr == > None` will actually compare all elements to None. (A FutureWarning for > now) This is a very useful change in behavior--thanks! Stéfan _

Re: [Numpy-discussion] Numpy arrays vs typed memoryviews

2014-01-25 Thread Sturla Molden
I think I have said this before, but its worth a repeat: Pickle (including cPickle) is a slow hog! That might not be the overhead you see, you just haven't noticed it yet. I saw this some years ago when I worked on shared memory arrays for Numpy (cf. my account on Github). Shared memory really

Re: [Numpy-discussion] using loadtxt to load a text file in to a numpy array

2014-01-25 Thread Charles R Harris
On Thu, Jan 23, 2014 at 11:49 AM, Chris Barker wrote: > Thanks for poking into this all. I've lost track a bit, but I think: > > The 'S' type is clearly broken on py3 (at least). I think that gives us > room to change it, and backward compatibly is less of an issue because it's > broken already --

Re: [Numpy-discussion] Catching out-of-memory error before it happens

2014-01-25 Thread Daπid
On 24 January 2014 23:09, Dinesh Vadhia wrote: > Francesc: Thanks. I looked at numexpr a few years back but it didn't > support array slicing/indexing. Has that changed? > No, but you can do it yourself. big_array = np.empty(2) piece = big_array[30:-50] ne.evaluate('sqrt(piece)') Here, c

Re: [Numpy-discussion] Comparison changes

2014-01-25 Thread Sebastian Berg
On Sat, 2014-01-25 at 00:18 +, Nathaniel Smith wrote: > On 25 Jan 2014 00:05, "Sebastian Berg" > wrote: > > > > Hi all, > > > > in https://github.com/numpy/numpy/pull/3514 I proposed some changes > to > > the comparison operators. This includes: > > > > 1. Comparison with None will broadcast i