[MATLAB] benchmark for parsing cell-array of strings

Readme.md

See Stack Overflow question: http://stackoverflow.com/q/26528999/97160

bench_runner.m

function t = bench_runner(fcns, p_rows, p_cols)
    out = cell(0,4);
    fnames = cellfun(@func2str, fcns, 'Uniform',false);

    % parameters sweep
    [nrows,ncols] = ndgrid(p_rows, p_cols);
    nrows = nrows(:); ncols = ncols(:);

    for k=1:numel(nrows)
        % generate data of specified size
        fprintf('=== %dx%d ===\n', nrows(k), ncols(k));
        words = rand_cellstr(nrows(k), ncols(k));
        
        % check results are equal
        fprintf('Checking output... ')
        v = cellfun(@(f) feval(f,words), fcns, 'UniformOutput',false);
        if ~isequal(v{:})
            fprintf('FAIL\n')
            continue
        else
            fprintf('PASS\n')
        end
        clear v

        % time functions, and store results
        for f=1:numel(fcns)
            fprintf('%40s: ', fnames{f});
            if ~isempty(strfind(fnames{f}, '_gpu'))
                tsec = gputimeit(@() feval(fcns{f}, words), 1);
            else
                tsec = timeit(@() feval(fcns{f}, words), 1);
            end
            fprintf('%f\n', tsec);
            out(end+1,:) = {fnames{f}, nrows(k), ncols(k), tsec}; %#ok<AGROW>
        end
    end
    
    % plot results, and return them as a table
    t = bench_plot_results(out);
end

function C = rand_cellstr(M,N)
    frmt = [repmat('%d_',1,N-1) '%d'];
    C = strrep(cellstr(num2str(randi([0 9999], [M N]), frmt)),' ','');
end

%{
% a lighter version of TIMEIT if you don't want to waste hours :)
function t = timeit(f, nout)
    if nargin < 2, nout = 1; end
    out = cell(1,nout);
    N = 5;         % number of repetitions
    t = zeros(N,1);
    f();f();f();   % warm up function
    for i=1:N
        tocId = tic;
        [out{:}] = feval(f);
        t(i) = toc(tocId);
    end
    t = mean(t);
end
%}

function t = bench_plot_results(out)
    %% pivot table
    t = cell2table(out, 'VariableNames',{'func', 'nrows', 'ncols', 'time'});
    tt = unstack(t, 'time', 'func');

    % prepare data for plotting
    y = tt{:,3:end}.';
    fnames = tt.Properties.VariableNames(3:end);
    x = 1:numel(fnames);
    str = strtrim(cellstr(num2str(tt{:,1:2},'%dx%d')));

    % sort by times
    [~,ord] = sortrows(y, -(size(y,2):-1:1));
    y = y(ord,:);
    fnames = fnames(ord);

    %% plot
    pos = get(0,'DefaultFigurePosition');

    figure(1), set(gcf, 'Position',pos.*[1 1 1.2 1.75]), movegui(gcf,'east')
    plot(y, x, 'Marker','.', 'MarkerSize',20, 'LineWidth',2)
    set(gca, 'YTick',x, 'YTickLabel',fnames, 'YLim',[0 x(end)+1], ...
        'XGrid','on', 'YGrid','on', 'XScale','log')
    xlabel('Time [sec]'), ylabel('Functions')
    legend(str, 'Orientation','horiz', 'Location','NorthOutside')

    figure(2), set(gcf, 'Position',pos.*[1 1 1.2 1.75]), movegui(gcf,'west')
    barh(x, y, 1.0, 'EdgeColor','k')
    set(gca, 'YTick',x, 'YTickLabel',fnames, 'YLim',[0 x(end)+1], ...
        'XGrid','on', 'XScale','log', 'YAxisLocation','right')
    xlabel('Time [sec]'), ylabel('Functions')
    legend(str, 'Orientation','horiz', 'Location','NorthOutside')
end

bench_script.m

% get list of available functions
% (I'm assuming necessary folders are already added to MATLAB path)
d = dir(fullfile('bench_functions','*.m'));
[~,f] = cellfun(@fileparts, {d(~[d.isdir]).name}, 'Uniform',false);

% filter out ones known to be slow!
f(strncmpi(f, 'func_str2double_', numel('func_str2double_'))) = [];

% function handles
fcns = cellfun(@str2func, f, 'Uniform',false)';

% run benchmarks and show report
t = bench_runner(fcns, 10.^(1:5), 10.^(1:1))