Octave Basics: Difference between revisions

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(→‎Graphics: Overhaul.)
(Improve syntaxhighlight.)
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<code>:</code> , <code>.*</code> , <code>./</code> , <code>.^</code> , <code>'</code> , <code>.'</code> , <code>\</code> , {{manual|length}} , {{manual|numel}} , {{manual|size}} , {{manual|zeros}} , {{manual|ones}} , {{manual|eye}} , {{manual|diag}} , {{manual|rand}} , {{manual|det}} , {{manual|trace}} , {{manual|inv}} , {{manual|lu}} , {{manual|eig}} , {{manual|cond}} , {{manual|expm}}
<code>:</code> , <code>.*</code> , <code>./</code> , <code>.^</code> , <code>'</code> , <code>.'</code> , <code>\</code> , {{manual|length}} , {{manual|numel}} , {{manual|size}} , {{manual|zeros}} , {{manual|ones}} , {{manual|eye}} , {{manual|diag}} , {{manual|rand}} , {{manual|det}} , {{manual|trace}} , {{manual|inv}} , {{manual|lu}} , {{manual|eig}} , {{manual|cond}} , {{manual|expm}}


  x = 1:5, x(:), x(2:4), A = [11 12; 21, 22], A(1,1:end) &crarr;
<syntaxhighlight lang="octave">
x = 1:5, x(:), x(2:4), A = [11 12; 21, 22], A(1,1:end)
</syntaxhighlight>


=== Graphics ===
=== Graphics ===
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{{manual|plot}} , {{manual|semilogx}} , {{manual|semilogy}} , {{manual|loglog}} , {{manual|contour}} , {{manual|quiver}} , {{manual|surf}} , {{manual|mesh}} , {{manual|meshgrid}} , {{manual|xlabel}} , {{manual|ylabel}} , {{manual|zlabel}} , {{manual|title}} , {{manual|grid}} , {{manual|axis}} , {{manual|hold}} , {{manual|subplot}} , {{manual|figure}} , {{manual|print}}
{{manual|plot}} , {{manual|semilogx}} , {{manual|semilogy}} , {{manual|loglog}} , {{manual|contour}} , {{manual|quiver}} , {{manual|surf}} , {{manual|mesh}} , {{manual|meshgrid}} , {{manual|xlabel}} , {{manual|ylabel}} , {{manual|zlabel}} , {{manual|title}} , {{manual|grid}} , {{manual|axis}} , {{manual|hold}} , {{manual|subplot}} , {{manual|figure}} , {{manual|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) &crarr;
<syntaxhighlight lang="octave">
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)
</syntaxhighlight>


=== Scripts and functions ===
=== Scripts and functions ===


<tt>@ | function | return | nargin | nargout | varargin | varargout | feval | eval</tt>
<tt>@ | function | return | nargin | nargout | varargin | varargout | feval | eval</tt>
f = @(x) x.^2, f(1:10) &crarr;


function v = cossum (x, n) v = cumsum (repmat (cos (x), 1, n));
<syntaxhighlight lang="octave">
f = @(x) x.^2, f(1:10)
 
function v = cossum (x, n) v = cumsum (repmat (cos (x), 1, n));
</syntaxhighlight>


=== Programming elements ===
=== Programming elements ===


<tt>== | > | < | >= | <= | != | | || | | & | && | ! | if | else | elseif | for | while |end | break | continue | pause</tt>
<tt>== | > | < | >= | <= | != | | || | | & | && | ! | if | else | elseif | for | while |end | break | continue | pause</tt>
for i = 1:5 if (i < 3) disp (i) else disp (i^2) end end &crarr;
 
<syntaxhighlight lang="octave">
for i = 1:5 if (i < 3) disp (i) else disp (i^2) endif endfor
</syntaxhighlight>


== See also ==
== See also ==

Revision as of 17:28, 14 June 2019

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