Octave Basics

For the meaning of operators, see the GNU Octave manual.

The very basics

+ , - , * , / , ^ , pi , I , e , inf , eps , sin , cos , tan , exp , log , log10 , abs , sqrt , sign , round , ceil , floor , fix , = , , , ; , who , clear , help , lookfor

x = pi, y = floor (sin (x)), z = log (exp (2013)), z / inf

Vectors and matrices

: , .* , ./ , .^ , ' , .' , \ , length , numel , size , zeros , ones , eye , diag , rand , det , trace , inv , lu , eig , cond , expm

x = 1:5, x(:), x(2:4), A = [11 12; 21, 22], A(1,1:end)

Graphics

plot , semilogx , semilogy , loglog , contour , quiver , surf , mesh , meshgrid , xlabel , ylabel , zlabel , title , grid , axis , hold , subplot , figure , print

t = 0:0.01*pi:21*pi; x = sin (t).*(exp (cos (t)) - 2*cos (4*t) + sin (t/12).^5); y = cos (t).*(exp (cos (t)) - 2*cos (4*t) + sin (t/12).^5); plot(x, y)

Scripts and functions

@ , function , return , nargin , nargout , varargin , varargout , feval , eval

f = @(x) x.^2, f(1:10)

function v = cossum (x, n) v = cumsum (repmat (cos (x), 1, n));

Programming elements

== , > , < , >= , <= , != , | , || , & , && , ! , ~ , if , else , elseif , for , while , end , break , continue , pause

for i = 1:5 if (i < 3) disp (i) else disp (i^2) endif endfor

See also

• GNU OCTAVE CARD by Fotios Kasolis