Matlab Cheat sheet

cheatsheet.matlab

% Matlab cheat sheet
% Author: Steven Van Vaerenbergh
% Last version: https://gist.github.com/steven2358/7578242


%% SYSTEM

% seed a random generator
seed = 1;
rng('default');
rng(seed);

% seed a random generator (explicit)
seed = 1;
s = RandStream('mt19937ar','Seed',seed);
RandStream.setGlobalStream(s);

% unique date string (time stamp)
datestr(now,30)

% get computer / host name
hostname = getenv('computername');

% check if a variable exists
a = exist('dataset','var');

% make folder if it does not exist
if exist('myfolder','dir') ~= 7
    mkdir('myfolder');
end

% list all .txt files in a folder, and get filenames without extensions
BASE_DIR = 'C:\path\to\directory';
files = dir(fullfile(BASE_DIR,'*.txt'));
[~,files] = cellfun(@fileparts, {files.name}, 'UniformOutput',false);

% measure and store time since specified tic
aa = tic;
bb = toc(aa);

% swap variables
[c,a,b]  = deal(a,b,c);

%% INTERFACE

% beep sound
soundsc(sin(1:1E4));

% beep sound (1 second, 440 Hz)
soundsc(sin(2*pi*440*(0:1/8192:1)));

% 10 progress dots
for n=1:N
    if ~mod(n,floor(N/10)), fprintf('.'); end
end
fprintf('\n')


%% STRINGS

% replace a substring
strrep('This is a good example.', 'good', 'great');

% find a string in a cell array
strs = {'apples','oranges','bananas'};
ind = find(ismember(strs,'oranges'));

% find a substring (pattern) within a string
k = strfind(str, pattern);

% sum the digits of a number x
sum(num2str(x) - '0');


%% SIGNAL PROCSESING

% add SNR to signal x
sigpow = x'*x/length(x);
noisepow = 10^(-SNR/10)*sigpow;


%% FIGURES

% legend location
legend('mytitle','Location','SW');

% remove legend box
legend boxoff

% set position and size of figure
set(gcf,'Position',[500 400 400 150])

% get standard colors
colors = get(gcf,'DefaultAxesColorOrder');

% set font and font size
set(gca, 'FontName', 'Times New Roman');
set(gca, 'FontSize', 11);

% set axis limits
axis([x1 x2 y1 y2])

% change only one limit of an axis
xlim([0 1])

% alternative way to change axis
xlim = get(gca,'XLim');
ylim = get(gca,'YLim');
axis([xlim(1) 0 ylim(1) ylim(2)])

% set the x-axis to logarithmic scale
set(gca,'XScale','log');

% expand figure axes
f = gcf;
style = hgexport('factorystyle'); style.Bounds = 'tight';
hgexport(f,'-clipboard',style,'applystyle', true);
drawnow;

% print PNG figure
print('-dpng','-r300',myfilename);

% print color EPS figure
print('-depsc2','-r300',myfilename);

% fix line style (using
% http://www.mathworks.com/matlabcentral/fileexchange/17928-fixpslinestyle)
fixPSlinestyle([myfilename '.eps'])

% formatted text box. Extra arguments: FontName, FontSize, FontWeight
axes('position',[0 0 1 1],'visible','off')
text(0.5,0.6,'mytext')

% setting ticks and labels
set(gca,'XTick',0:10:100)
set(gca,'XTickLabel',{'A','B'})

% change plot interpreter to tex or latex
ylabel('$\alpha$','Interpreter','LaTex')

% Greek letters in tick labels
str=['p/2';'p']; % \pi/2, \pi
set(gca,'xticklabel',str,'fontname','symbol')

% change aspect ratios for different axes
set(gca,'dataaspectratio',[1,1,.5]);

% save figure in .fig format
saveas(gcf, 'path', 'fig');

% transparant bg
set(gcf, 'InvertHardcopy', 'off')

% extract data from plot
h = findobj(gca,'Type','line');
x=get(h,'Xdata');
y=get(h,'Ydata');

% get standard colors
colors = get(0,'DefaultAxesColorOrder');