Cannot Use 128bit Float In Python On 64bit Architecture

I checked the size of a pointer in my python terminal (in Enthought Canopy IDE) via import ctypes print (ctypes.sizeof(ctypes.c_voidp) * 8) I've a 64bit architecture and working

Solution 1:

Update: From the comments, it seems pointless to even have a 128 bit float on a 64 bit system.

I am using anaconda on a 64-bit Ubuntu 14.04 system with sys.version_info(major=2, minor=7, micro=9, releaselevel='final', serial=0)

and 128 bit floats work fine:

importnumpya= numpy.float128(3)

This might be an distribution problem. Try:

• Install Anaconda
• Update canopy
• Check that the version of python in the path is the one supplied by anaconda or canopy

EDIT: Update from the comments:

Not my downvote, but this post doesn't really answer the "why doesn't np.float128 exist on my machine" implied question. The true answer is that this is platform specific: float128 exists on some platforms but not others, and on those platforms where it does exist it's almost certainly simply the 80-bit x87 extended precision type, padded to 128 bits. – Mark Dickinson

Solution 2:

For me, the issue was a Python module that has a problem in Windows (PyOpenGL for those that care). This site has Python wheels with "fixed" versions of many popular modules, to address the float128 issue.

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Note: This question has an accepted answer. My answer if for future searchers, since this question is high in Google results for module 'numpy' has no attribute 'float128'.