高等应用数学问题的MATLAB求解02.ppt

Slide 1 (of 11) Chapter 2Fundamentals of MATLABProgramming Chapter 2 Fundamentals of MATLAB Programming Fundamentals of MATLAB Programming Fundamental Mathematical Calculations Flow Control Structures of MATLAB Language Writing and Debugging MATLAB Functions Two-dimensional Graphics Three-dimensional Graphics Chapter summary MATLAB has the following advantages: Clarity and high efficiency Scientific computation, covers almost all the useful topics in math and engineering Graphics facilities Comprehensive toolboxes and block-sets, designed by experts of almost all disciplines Powerful simulation facilities, unite the sub-systems of different domains together 2.1 Fundamentals of MATLAB Programming Variables and constants in MATLAB Data structures Basic structure of MATLAB Colon expressions and sub-matrices extraction 2.1.1 Variables and constants in MATLAB Variables in MATLAB Starting with a letter followed by other characters: Case-sensitive: Valid variable names: MYvar12, MY_Var12 and MyVar12_ Invalid variable names: 12MyVar, _MyVar12 Constants in MATLAB: eps, i, j, pi, NaN, Inf, i=sqrt(-1) lastwarn, lasterr 2.1.2 Data structures Double-precision data type Symbolic data type Other data types Double-precision data type IEEE standard, 64 bits (8 bytes)，11 bits for exponential and 53 bits for numerical and a sign bit. Use double() to convert other types to double. Data range: Other data types: int8(), int16(), int32(), uint16(), uint32() Symbolic data type Usually used in formula derivations and analytical solutions variable declaration display the symbolic variables in any precision The default value: 32 decimal digits. Example 2.1 Display the first 300 digits of . MATLAB command One may further increase the number of digits to display. For extremely large number of digits, process may be slow Other data types Strings: String variables are used to store messages. Multi-dimensional arrays: a direct extension of matrices with multiple indices. Cell ar