QtOctave Help.


QtOctave is a Graphical User Interface for Gnu Octave

QtOctave is a graphical user interface for gnu octave, which is an open source program alternative to Matlab.  With QtOctave you can do perform computationally intensive mathematical tasks that would take much longer to code in C or C++ or practically any other modern computer language.  It is especailly good at matrix and vector operations.  The graphical capabilities are very advanced.  It is used heavily in engineering, and is a tool well worth learning.

This document describes how to use QtOctave.  It does not describe using octave.  Octave help is available from the menu Help->Octave Help or by clicking the Help Icon button on the toolbar.  Often tool tips are available by hovering the mouse over the various tools.

File

Open New QtOctave Window

Editor

Run an Octave Script

Change Directory

View

Windows Layout

Save or load actual windows configuration.

Toolbars

Select here the toolbars you wish to display on the Octave window.

Docks

Select which panels are open.

Show/Hide objects

It shows or hides tools of QtOctave.

Analysis

Tools to solve differential equations or integrate functions.

Data

A graphical way to enter and save matrices

Equations

A graphical interface to solving equations

Matrix

A graphical interface to common matrix operations

Statistics

A graphical interface to some statistical functions including...

Plot

A graphical interface to plotting functions

SvgCanvas

You can show plots in SVG file format. You can export then to PDF, PNG,... Qt supports the static features of SVG 1.2 Tiny. ECMA scripts and DOM manipulation are currently not supported. You can find documentation about SVG in SVG 1.2 Tiny
QtOctave has several functions to work with SVG file format:
svgcanvasload(n, file_name)
Shows file_name in window n. File_name must be absolute path.
Example:
 svgcanvasload(1, '/home/user/ej1.svg')

svgcanvassave(n, width, height, file_name)
Saves plot in window n in file file_name. File_name must be absolute path. File_name can be a PDF, PNG, JPEG, PS,... file format.
Example:
 svgcanvassave(1, 200, 200, '/home/user/ej1.jpg')
 svgcanvassave(1, 200, 200, '/home/user/ej1.pdf')

svgcanvas_delete_on_load(n, file_name)
Shows file_name in window n. file_name is deleted. File_name must be absolute path. This command is very useful for animations.
Example:
 svgcanvas_delete_on_load(1, '/home/user/ej1.svg')

This is an example of SvgCanvas. It plots a Lissajous figure of phase phase, and frequency ratio w:
function ej(w, phase)
	if(!exist('w'))
		w=2;
		phase=pi/4;
	endif
	out=fopen("ej9.svg", "w");
	fprintf(out, '<?xml version="1.0" standalone="yes"?>\n');
	fprintf(out, '<svg width="200" height="200" version="1.1">\n');
	fprintf(out, '<path d="M %f %f', 200, 100-100*sin(phase) );
	n=1000;
	for k=1:n
		fprintf(out, " L %f %f", 100+100*cos(k/n*2*pi), 100-100*sin(w*k/n*2*pi+phase) );
	endfor
	fprintf(out, '" fill="none" stroke="black" stroke-width="1"/>\n');
	fprintf(out, '</svg>\n');
	fclose(out);
	disp("Ok");
	file_name=sprintf("%s/ej9.svg", pwd);
	svgcanvasload(1, file_name );
endfunction

Configuration

General Configuration

Set up things that are specific to your system.

Octave

Help

Editor

Terminal

Help

* Build your own QtOctave menus.