Numerical Analysis First Term Dr. Selcuk CANKURT

Transcription

1 ISHIK UNIVERSITY FACULTY OF ENGINEERING and DEPARTMENT OF COMPUTER ENGINEERING Numerical Analysis First Term Dr. Selcuk CANKURT

2 Textbook Main Textbook MATLAB for Engineers, 4/e Holly Moore, 2015, Pearson. Supplementary Textbook Engineers Guide to MATLAB, An, 3/E Edward B. Magrab 2011 by Prentice Hall. MATLAB - An Introduction with Applications, 5th edition, GILAT

3 COURSE Code Name Level Year Semester CMPE 204 Numerical Analysis BS Undergraduate II Spring Status Number of ECTS Credits Class Hours Per Week Total Hours Per Semester Main Course

4 ASSESSMENT METHODS STUDENT ASSESSMENT METHODS Class participation and activities 10% Lab 15% Homework 15% Midterm Examination 20% Final Examination 40%

5 Variables The name of a variable in MATLAB has to start with a letter. After that, the name can consist of an arbitrary number of letters, numbers or symbols like '_' and '-'. MATLAB does distinguish between upper and lower case letters. Data Type Matlab Class Name Explanation Example Floating-Point Numbers Single, Double This is the default data type in Matlab. They are used to store real numbers. a = Integers int8, uint8, int16, uint16, int32, uint32, int64, uint64 This data type is for storage of whole numbers. "u" stands for unsigned integers while "8,16,32,64" stand for the number of bits for storage. b = uint16(256) Characters and Strings char Used to store text. A string is an array of characters while char signifies each one. c = 'Hello World' Boolean logical Used to store true (1) or false (0). d= true; Structures struct Used to store varying lengths and types of data. The data is accessed using a name. A = struct('name', {'Ahmed','Saligbeg'},'Scores', [6 3 5]); Cell Arrays cell Used to store varying lengths and types of data. The data is accessed using an index. A = cell(2)

6 Predefined variables in MATLAB Variable ans eps i or j Explanation This variable contains the result of the last calculation that has not been assigned to another variable. The value of this variable is approximately and is being used internally by MATLAB. This number is the default computation accuracy of MATLAB which is used to round of all numbers for storage in the computer memory. The complex number pi Inf NaN This is the value infinity. When one divides 1 by 0, 1/0, the result will be Inf. This variable is a representation of `Not a Number'. A calculation with NaN always results in NaN. The command 0/0 produces NaN.

7 Mathematical expressions MATLAB sin(x) Standard operations sqrt(x) cos(x) exp(x) tan(x) log(x) asin(x) log10(x)

8 The order of operations in MATLAB is the standard order: first parentheses secondly raising to a power, then multiplication and division, and after that addition and subtraction. e.g. is obtained by executing 1/(exp(3)+1). Interruption A (long) MATLAB calculation can be interrupted with `ctrl-c'.

9 Command who whos clear Explanation Gives a list of the variables in use. Gives a list of the variables in use as well as some extra information. Removes all variables. clear x y Removes the variables x and y. clc help lookfor quit Clears command window. Searches for a help topic. Searches help entries for a keyword. Stops MATLAB.

10 Format Function format short format long format short e format long e format bank format + format rat format compact format loose Display up to Four decimal digits (default). 16 decimal digits. Five digits plus exponent. 16 digits plus exponents. Two decimal digits. Positive, negative, or zero. Rational approximation. Suppresses some line feeds. Resets to less compact display mode.

11 Input and Output Commands Command disp fscanf format fprintf input Purpose Displays contents of an array or string. Read formatted data from a file. Controls screen-display format. Performs formatted writes to screen or file. Displays prompts and waits for input. ; Suppresses screen printing.

12 The fscanf and fprintf commands behave like C scanf and printf functions. They support the following format codes Format Code Purpose %s Format as a string. %d Format as an integer. %f Format as a floating point value. %e Format as a floating point value in scientific notation. %g Format in the most compact form: %f or %e. \n Insert a new line in the output string. \t Insert a tab in the output string.