我有一个来自this source的Matlab代码示例。只有函数,没有像python语言这样的初始起点。以下是代码概述:
运行的函数序列是什么?换句话说,哪个功能首先运行,哪个功能运行等等?
这是完整的代码:
function [net, info] = cnn_mnist(varargin)
%CNN_MNIST Demonstrates MatConvNet on MNIST
run(fullfile(fileparts(mfilename('fullpath')),...
'..', '..', 'matlab', 'vl_setupnn.m')) ;
opts.batchNormalization = false ;
opts.networkType = 'simplenn' ;
[opts, varargin] = vl_argparse(opts, varargin) ;
sfx = opts.networkType ;
if opts.batchNormalization, sfx = [sfx '-bnorm'] ; end
opts.expDir = fullfile(vl_rootnn, 'data', ['mnist-baseline-' sfx]) ;
[opts, varargin] = vl_argparse(opts, varargin) ;
opts.dataDir = fullfile(vl_rootnn, 'data', 'mnist') ;
opts.imdbPath = fullfile(opts.expDir, 'imdb.mat');
opts.train = struct() ;
opts = vl_argparse(opts, varargin) ;
if ~isfield(opts.train, 'gpus'), opts.train.gpus = []; end;
% --------------------------------------------------------------------
% Prepare data
% --------------------------------------------------------------------
net = cnn_mnist_init('batchNormalization', opts.batchNormalization, ...
'networkType', opts.networkType) ;
if exist(opts.imdbPath, 'file')
imdb = load(opts.imdbPath) ;
else
imdb = getMnistImdb(opts) ;
mkdir(opts.expDir) ;
save(opts.imdbPath, '-struct', 'imdb') ;
end
net.meta.classes.name = arrayfun(@(x)sprintf('%d',x),1:10,'UniformOutput',false) ;
% --------------------------------------------------------------------
% Train
% --------------------------------------------------------------------
switch opts.networkType
case 'simplenn', trainfn = @cnn_train ;
case 'dagnn', trainfn = @cnn_train_dag ;
end
[net, info] = trainfn(net, imdb, getBatch(opts), ...
'expDir', opts.expDir, ...
net.meta.trainOpts, ...
opts.train, ...
'val', find(imdb.images.set == 3)) ;
% --------------------------------------------------------------------
function fn = getBatch(opts)
% --------------------------------------------------------------------
switch lower(opts.networkType)
case 'simplenn'
fn = @(x,y) getSimpleNNBatch(x,y) ;
case 'dagnn'
bopts = struct('numGpus', numel(opts.train.gpus)) ;
fn = @(x,y) getDagNNBatch(bopts,x,y) ;
end
% --------------------------------------------------------------------
function [images, labels] = getSimpleNNBatch(imdb, batch)
% --------------------------------------------------------------------
images = imdb.images.data(:,:,:,batch) ;
labels = imdb.images.labels(1,batch) ;
% --------------------------------------------------------------------
function inputs = getDagNNBatch(opts, imdb, batch)
% --------------------------------------------------------------------
images = imdb.images.data(:,:,:,batch) ;
labels = imdb.images.labels(1,batch) ;
if opts.numGpus > 0
images = gpuArray(images) ;
end
inputs = {'input', images, 'label', labels} ;
% --------------------------------------------------------------------
function imdb = getMnistImdb(opts)
% --------------------------------------------------------------------
% Preapre the imdb structure, returns image data with mean image subtracted
files = {'train-images-idx3-ubyte', ...
'train-labels-idx1-ubyte', ...
't10k-images-idx3-ubyte', ...
't10k-labels-idx1-ubyte'} ;
if ~exist(opts.dataDir, 'dir')
mkdir(opts.dataDir) ;
end
for i=1:4
if ~exist(fullfile(opts.dataDir, files{i}), 'file')
url = sprintf('http://yann.lecun.com/exdb/mnist/%s.gz',files{i}) ;
fprintf('downloading %s\n', url) ;
gunzip(url, opts.dataDir) ;
end
end
f=fopen(fullfile(opts.dataDir, 'train-images-idx3-ubyte'),'r') ;
x1=fread(f,inf,'uint8');
fclose(f) ;
x1=permute(reshape(x1(17:end),28,28,60e3),[2 1 3]) ;
f=fopen(fullfile(opts.dataDir, 't10k-images-idx3-ubyte'),'r') ;
x2=fread(f,inf,'uint8');
fclose(f) ;
x2=permute(reshape(x2(17:end),28,28,10e3),[2 1 3]) ;
f=fopen(fullfile(opts.dataDir, 'train-labels-idx1-ubyte'),'r') ;
y1=fread(f,inf,'uint8');
fclose(f) ;
y1=double(y1(9:end)')+1 ;
f=fopen(fullfile(opts.dataDir, 't10k-labels-idx1-ubyte'),'r') ;
y2=fread(f,inf,'uint8');
fclose(f) ;
y2=double(y2(9:end)')+1 ;
set = [ones(1,numel(y1)) 3*ones(1,numel(y2))];
data = single(reshape(cat(3, x1, x2),28,28,1,[]));
dataMean = mean(data(:,:,:,set == 1), 4);
data = bsxfun(@minus, data, dataMean) ;
imdb.images.data = data ;
imdb.images.data_mean = dataMean;
imdb.images.labels = cat(2, y1, y2) ;
imdb.images.set = set ;
imdb.meta.sets = {'train', 'val', 'test'} ;
imdb.meta.classes = arrayfun(@(x)sprintf('%d',x),0:9,'uniformoutput',false);
答案 0 :(得分:4)
在MATLAB中,当在同一文件中定义多个函数时,第一个函数定义是使用包含.m
文件的名称执行文件时执行的函数定义。除非从第一个函数(或另一个子函数)调用它们,否则该文件中的所有其他子函数都不会被执行。在MATLAB中,如果没有首先通过main函数,就无法访问子函数。
另请注意,即使第一个函数的名称与cnn_mnist
文件的名称不匹配,该函数仍将仍然是执行的函数。如果您的函数名称与文件名不匹配,您应该会收到一个指示此情况的mlint警告。
对于您的特定代码,执行代码时会调用getMnistImdb
。此函数调用子函数getBatch
和getSimpleNNBatch
,然后调用getDagNNBatch
和{{1}}