openblas

I have both BLAS and OpenBLAS installed: $ dpkg -l \*blas\* | grep ^i ii libblas-dev 1.2.20110419-7 amd64 Basic Linear Algebra Subroutines 3, static library ii libblas3 1.2.20110419-7 amd64 Basic Linear Algebra Reference implementations, shared library ii libopenblas-base 0.2.8-6ubuntu1 amd64 Optimized BLAS (linear algebra) library based on GotoBLAS2 ii libopenblas-dev 0.2.8-6ubuntu1 amd64 Optimized BLAS (linear algebra) library based on GotoBLAS2 However, NumPy still says that OpenBLAS is not available: >> np.__config__.show() blas_info: libraries = ['blas'] library_dirs = ['/usr/lib']

I have a C/C++ program which involves intensive 32-bit floating-point matrix math computations such as addition, subtraction, multiplication, division, etc. Can I speed up my program by converting 32-bit floating-point numbers into 16-bit fixed-point numbers ? How much speed gain can I get ? Currently I'm working on a Intel I5 CPU. I'm using Openblas to perform the matrix calculations. How should I re-implement Openblas functions such as cblas_dgemm to perform fixed-point calculations ? I know that SSE(Simple SIMD Extensions) operates on 4x32=8x16=128 bit data at one time, i.e., 4 32-bit

I wanted to install BLAS, CBLAS, LAPACK and OpenBLAS libraries from source using available packages you can download here openblas and lapack , blas/cblas . Firstly I removed my system blas/cblas and lapack libraries, but unfortunately atlas library couldn't be uninstalled (I can either have both blas and lapack or atlas - can't remove them all). I didn't bother and started compiling downloaded libraries cause I thought that after installation I would be able to remove atlas. Building process was based on this tutorial. For completeness I will list the steps: OpenBLAS . After editing Makefile

In particular, I would like to know if xianyi's OpenBLAS has been installed. I work on several PCs and had it installed in several PCs over the past couple of years, but I lost track which were not installed with it. I need to know which PC has it and which doesn't This is how I installed it: git clone git://github.com/xianyi/OpenBLAS cd OpenBLAS make FC=gfortran sudo make PREFIX=/usr/local/ install Note: I may have deleted the OpenBLAS directory, so it's not a reliable indicator. And I have no idea how to uninstall it, so I can't try installing it on every PC and then uninstall selectively

Is it possible to install openblas via apt-get like sudo apt-get install openblas-dev ? Seems on ubuntu 14.04 it can't find it. sudo apt-get install openblas-dev Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package openblas-dev apt-cache search openblas libblas-test - Basic Linear Algebra Subroutines 3, testing programs libopenblas-base - Optimized BLAS (linear algebra) library based on GotoBLAS2 libopenblas-dev - Optimized BLAS (linear algebra) library based on GotoBLAS2 So sudo apt-get install libopenblas-dev solved the problem.

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: Running Ubuntu 11.10 + python2.7...built numpy from source and installed it, but when I go to install it, I get ImportError : /usr/ lib / liblapack . so . 3gf : undefined symbol : ATL_chemv when it tries to import lapack_lite from numpy.linalg. I tried to rebuild lapack from scratch, but it seems to just make /usr/ local / lib / libblas . a / usr / local / lib / liblapack . a / usr / local / lib / libtmglib . a and the .so file. Where does the .so.3gf come from, and how do I fix it? 回答1: I was having the same problem and removing

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I wanted to install BLAS, CBLAS, LAPACK and OpenBLAS libraries from source using available packages you can download here openblas and lapack , blas/cblas . Firstly I removed my system blas/cblas and lapack libraries, but unfortunately atlas library couldn't be uninstalled (I can either have both blas and lapack or atlas - can't remove them all). I didn't bother and started compiling downloaded libraries cause I thought that after installation I would be able to remove atlas. Building process was based on this tutorial. For completeness I

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: How should I fix this? Monas-MacBook-Pro:02_02 mona$ python Python 3.6.1 |Anaconda custom (x86_64)| (default, May 11 2017, 13:04:09) [GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.57)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import cv2 Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: dlopen(/Users/mona/anaconda/lib/python3.6/site-packages/cv2.cpython-36m-darwin.so, 2): Library not loaded: @rpath/libopenblasp-r0.2.19.dylib Referenced from: /Users/mona/anaconda

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: I am trying to install Theano on Windwos 8 Have followed these steps. I try to test using: import numpy as np import time import theano print ( 'blas.ldflags=' , theano . config . blas . ldflags ) A = np . random . rand ( 1000 , 10000 ). astype ( theano . config . floatX ) B = np . random . rand ( 10000 , 1000 ). astype ( theano . config . floatX ) np_start = time . time () AB = A . dot ( B ) np_end = time . time () X , Y = theano . tensor . matrices ( 'XY' ) mf = theano . function ([ X , Y ], X . dot ( Y )) t_start = time . time (

类似于Anaconda里面的numpy，C++里面也有类似的矩阵运算库，称之为BLAS（Basic Linear Algebra Subprograms）：基础线性代数子程序库。 支持的数据类型有： 单精度浮点数（float） 双精度浮点数（double） 单精度负数 双精度负数 在机器学习里面一般我们只用float类型，很少使用double，考虑到性能，我们认为float的精度已经够了，而且速度快。 还有一个更高级的叫LAPACK，现在我们常用的BLAS其实就是LAPACK里面的一部分。 BLAS支持对子程序的封装，其实就是子函数了，它的子程序分类： Level1: 标量操作、向量操作、向量-向量操作 Level2：矩阵-向量操作 Level3: 矩阵-矩阵操作 BLAS：标准实现（Fortran） CBLAS：C的BLAS标准实现 Atlas：一种优化实现 GotoBLAS：多线程性能良好的优化实现（已停止更新） OpenBLAS：目前性能最好的开源实现，基于GotoBLAS MKL：Intel实现，在Intel处理器上性能最佳 各种BLAS实现的优劣对比 市面上的BLAS实现非常多，最早是用Fortran。 CBLAS是C的BLAS标准实现，但是这种实现有个缺点，速度非常慢。 Atlas：比C要好，但不够好。比如腾讯QQ空间有一个功能，就是标脸框那个程序，怎么做呢