CUV Documentation

Summary

CUV is a C++ template and Python library which makes it easy to use NVIDIA(tm) CUDA.

Features

Supported Platforms:

• This library was only tested on Ubuntu Karmic, Lucid and Maverick. It uses mostly standard components (except PyUBLAS) and should run without major modification on any current linux system.

Supported GPUs:

• By default, code is generated for the lowest compute architecture. We recommend you change this to match your hardware. Using ccmake you can set the build variable "CUDA_ARCHITECTURE" for example to –arch=compute_20
• All GT 9800 and GTX 280 and above
• GT 9200 without convolutions. It might need some minor modifications to make the rest work. If you want to use that card and have problems, just get in contact.
• On 8800GTS, random numbers and convolutions wont work.

Structure:

• Like for example Matlab, CUV assumes that everything is an n-dimensional array called "tensor"
• Tensors can have an arbitrary data-type and can be on the host (CPU-memory) or device (GPU-memory)
• Tensors can be column-major or row-major (1-dimensional tensors are, by convention, row-major)
• The library defines many functions which may or may not apply to all possible combinations. Variations are easy to add.
• For convenience, we also wrap some of the functionality provided by Alex Krizhevsky on his website (http://www.cs.utoronto.ca/~kriz/) with permission. Thanks Alex for providing your code!

Python Integration

• CUV plays well with python and numpy. That is, once you wrote your fast GPU functions in CUDA/C++, you can export them using Boost.Python. You can use Numpy for pre-processing and fancy stuff you have not yet implemented, then push the Numpy-matrix to the GPU, run your operations there, pull again to CPU and visualize using matplotlib. Great.

Implemented Functionality

• Simple Linear Algebra for dense vectors and matrices (BLAS level 1,2,3)
• Helpful functors and abstractions
• Sparse matrices in DIA format and matrix-multiplication for these matrices
• I/O functions using boost.serialization
• Fast Random Number Generator
• Up to now, CUV was used to build dense and sparse Neural Networks and Restricted Boltzmann Machines (RBM), convolutional or locally connected.

Documentation

• Tutorials are available on https://www.ais.uni-bonn.de/~schulz/tag/cuv
• The documentation can be generated from the code or accessed on the internet: https://www.ais.uni-bonn.de/deep_learning/doc/html/index.html

Contact

• We are eager to help you getting started with CUV and improve the library continuously! If you have any questions, feel free to contact Hannes Schulz (schulz at ais dot uni-bonn dot de) or Andreas Mueller (amueller at ais dot uni-bonn dot de). You can find the website of our group at https://www.ais.uni-bonn.de/deep_learning/index.html.

Installation

Requirements

For C++ libs, you will need:

• cmake (and cmake-curses-gui for easy configuration)
• libboost-dev >= 1.37
• libblas-dev
• NVIDIA CUDA (tm), including SDK. We support versions 3.X and 4.0
• thrust library - included in CUDA since 4.0 (otherwise available from http://code.google.com/p/thrust/)
• doxygen (if you want to build the documentation yourself)

For Python Integration, you additionally have to install

• pyublas – from http://mathema.tician.de/software/pyublas
• python-nose – for python testing
• python-dev

Optionally, install dependent libraries

• cimg-dev for visualization of matrices (grayscale only, ATM)

Obtaining CUV

You should check out the git repository

$ git clone git://github.com/deeplearningais/CUV.git

Installation Procedure

Building CUV:

$ sudo apt-get install cmake cmake-curses-gui libblas-dev libboost-all-dev doxygen python-nose python-dev cimg-dev
$ # download and install pyublas if you want python-bindings
$ cd cuv-version-source
$ mkdir -p build/release
$ cd build/release
$ cmake -DCMAKE_BUILD_TYPE=Release ../../
$ ccmake .          # adjust paths to your system (cuda, thrust, pyublas, ...)!
                    # turn on/off optional libraries (CImg, ...)
$ make -j
$ ctest             # run tests to see if it went well
$ sudo make install
$ export PYTHONPATH=`pwd`/src      # only if you want python bindings

On Debian/Ubuntu systems, you can skip the sudo make install step and instead do

$ cpack -G DEB
$ sudo dpkg -i cuv-VERSION.deb

Building the documentation

$ cd build/debug    # change to the build directory
$ make doc

Sample Code

We show two brief examples. For further inspiration, please take a look at the test cases implemented in the src/tests directory.

Pushing and pulling of memory

C++ Code:

#include <cuv.hpp>
using namespace cuv;

int main(void){
    tensor<float,host_memory_space> h(extents[8][5]);  // reserves space in host memory
    tensor<float,dev_memory_space>  d(extents[8][5]);  // reserves space in device memory

    h = 0;                              // set all values to 0

    d=h;                                // push to device
    sequence(d);                        // fill device vector with a sequence

    h=d;                                // pull to host
    for(int i=0;i<h.size();i++) {
        assert(d[i] == h[i]);
    }

    for(int i=0;i<h.shape(0);i++)
        for(int j=0;j<h.shape(1);j++) {
            assert(d(i,j) == h(i,j));
        }
}

Python Code:

import cuv_python as cp
import numpy as np

h = np.zeros((1,256))                                   # create numpy matrix
d = cp.dev_tensor_float(h)                              # constructs by copying numpy_array

h2 = np.zeros((1,256)).copy("F")                        # create numpy matrix
d2 = cp.dev_tensor_float_cm(h2)                         # creates dev_tensor_float_cm (column-major float) object

cp.fill(d,1)                                            # terse form
cp.apply_nullary_functor(d,cp.nullary_functor.FILL,1)   # verbose form

h = d.np                                                # pull and convert to numpy
assert(np.sum(h) == 256)
d.dealloc()                                             # explicitly deallocate memory (optional)

Simple Matrix operations

C++-Code

#include <cuv.hpp>
using namespace cuv;

int main(void){
    tensor<float,dev_memory_space,column_major> C(2048,2048),A(2048,2048),B(2048,2048);

    sequence(A);                        // fill A, B with consecutive integers
    sequence(B);

    apply_binary_functor(A,B,BF_MULT);  // elementwise multiplication
    A *= B;                             // operators also work (elementwise)
    prod(C,A,B, 'n','t');               // matrix multiplication
}

Python Code

import cuv_python as cp
import numpy as np
C = cp.dev_tensor_float_cm([2048,2048])   # column major tensor
A = cp.dev_tensor_float_cm([2048,2048])   
B = cp.dev_tensor_float_cm([2048,2048])
cp.sequence(A)
cp.sequence(B)
cp.apply_binary_functor(B,A,cp.binary_functor.MULT) # elementwise multiplication
B *= A                                              # operators also work (elementwise)
cp.prod(C,A,B,'n','t')                              # matrix multiplication

The examples can be found in the "examples/" folder under "python" and "cpp"