MATLAB

This can be done from the command line or from a makefile. You need a script (filename.m). Just type at the command line, or include in the makefile: matlab<filename.m where filename.m can write to disk a figure, a binary, an ascii file, anything you want.

We will run it from sthelens, and only if sthelens is down, from cher, orsay or tiree. It works on other machines too, but some of the other machines have older versions of the OS and core dump upon exiting from matlab. Some other local machines with new setups work fine. Try your local machine. Matlab is blocked from running on the servers

Matlab already handles naturally simple LaTeX encodings that allow introducing Greek lettters or modifying the font size and appearance in plots.

Thinking is terms of full matrices/vectors and also some related functions for that * Use of filter(), which works beautifully for some time series models

3D visualization elements allow MATLAB to deal with 3D graphics.

► Surface and Mesh Plots - It includes plot matrices, visualize functions, color maps.

► View Control - Used to control camera viewpoint, rotation, zooming, and aspect ratio and set axis limits.

► Lighting - Used for adding and controlling scene lighting.

► Transparency - Used to specify object transparency.

► Volume Visualization - Used for volume data grid.

Preallocating a block of memory for holding a non double matrix is memory efficient.

► It is faster to use the function 'repmat'.

► While allocating block of memory for a matrix, zeros are pre allocated to a matrix.

► The function to pre allocate memory is int8().

Ex: matrix = int8(zeros(100));

► Repmat function is used to create a single double matrix.

► Ex: matrix2 = repmat(int8(0), 100, 100);

► Thus non double matrix is pre allocated.

Simple calculations 2. Plotting and analyzing mathematical relationships (2D and 3D) 3. List & Matrix Operations 4. Writing script files (a type of programming) 5. Symbolic manipulation of equations 6. Advanced visualization, animation and GUI interface tools

Below is the list of memory management functions.

► Clear - Removes variables from memory.

► Pack - Saves the existing variables to disk, and then reloads them contiguously.

► Save - Selectively persists variables to disk.

► Load - Reloads a data file saved with the save function.

► Quit - Exits MATLAB and returns all allocated memory to the system.

Batch mode execution of MATLAB can be done from command line or from makefile.

► A script is needed with extension .m.

► Specify all the commands that are to execute in sequential order in the script.

► The commands are placed in the script by using the command makefile

► To add the commands in command line mode, type all the commands at the command line in sequential order.

► The commands are executed soon after typing them at the command line.

MATLAB allows Greek letters.

► These letters are to be encoded.

► To encode these Greek letters, LaTeX is used.

MATLAB already handles naturally simple LaTeX encodings that allow introducing Greek lettters or modifying the font size and appearance in plots.

Following is the sequence of commands to apply graphic patches in MATLAB.

► Open the LOCAL MACHINE window.

► Type the command xhost + ashland.

► Add the following code sequence before the plot command.

Figure;

Set(gcf,'renderer','zbuffer');

[s,w] = unix('echo $DISPLAY');

Set(gcf, 'XDisplay',w);

At times scripts need to run without displaying the plots.

► By doing this, the script statement need not be commented.

► When working from home, running graphics over the network may be too slow.

► To perform the process, add the following lines of code:

%setenv DISPLAY /dev/null % MATLAB.

► By using these simple tricks, we can run MATLAB without graphics.

Xmath is an interactive scripting and graphics environment for Xwindow workstations.

► With its significant improvement features on MATLAB-type software, interactive mathematics, scripting functionalities are elaborated.

► Following are the Xmath features:

► Sripting languages with OOP features.

► Libraries that are LNX and C language compatible.

► A debugging tools with GUI features.

► Color graphics can be pointed and clickable.

► A special layer is available that is programmable for MOTIF GUI.

Following is the list of image arithmetic functions and their usage.

► Imabsdiff - Returns absolute difference of two images.

► Imadd - Performs addition of two images or addition of constant to image.

► Imapplymatrix - Applies linear combination of color channels.

► Imcomplement - Complements an image.

► Imdivide - Divide one image into another or divide image by constant.

► Imlincomb - Linear combination of images.

► Immultiply - Multiplies two images or multiplies image by constant.

► Imsubtract - Subtracts one image from another or subtracts constant from image.

MatLab consists of five main parts

► MatLab Language

► MatLab working environment

► Handle Graphics

► MatLab function library

► MatLab Application Program Interface (API)

Simulink is an add-on product to MatLab, it provides an interactive, simulating, graphical environment for modeling and analyzing of dynamic systems.

Matlab allows following Operators

► Arithmetic Operators

► Relational Operators

► Logical Operators

► Bitwise Operations

► Set Operations

Matlab provides loops like

► While Loop

► For Loop

► Nested Loops

The four basic functions that MatLab has to solve ODE's are

► Quad

► Quad8

► ODE23

► ODE45

Graphic system used in MatLab is known as handle graphics. It has a high level and low-level commands.

► High Level Commands: High level command performs image processing, data visualization and animation for 2D and 3D presentation graphics

► Low Level Commands: Full customization of the appearance of graphics and building of complete graphical user interface