some+help+and+function

== code matlab code explaining ,,,,

code

code >> help elmat

Elementary matrices and matrix manipulation.

Elementary matrices. zeros      - Zeros matrix.零 ones       - Ones matrix. eye        - Identity matrix. rand       - Uniformly distributed random numbers. randn      - Normally distributed random numbers. linspace   - Linearly spaced vector. logspace   - Logarithmically spaced vector. meshgrid   - X and Y arrays for 3-D plots. :          - Regularly spaced vector.

Special variables and constants. ans        - Most recent answer. eps        - Floating point relative accuracy. realmax    - Largest floating point number. realmin    - Smallest positive floating point number. pi         - 3.1415926535897....   i, j        - Imaginary unit. inf        - Infinity. NaN        - Not-a-Number. flops      - Count of floating point operations. nargin     - Number of function input arguments. nargout    - Number of function output arguments. computer   - Computer type. isieee     - True for computers with IEEE arithmetic. isstudent  - True for the Student Edition. why        - Succinct answer. version    - MATLAB version number.

Time and dates. clock      - Wall clock. cputime    - Elapsed CPU time. date       - Calendar. etime      - Elapsed time function. tic, toc   - Stopwatch timer functions.

Matrix manipulation. diag       - Create or extract diagonals. fliplr     - Flip matrix in the left/right direction. flipud     - Flip matrix in the up/down direction. reshape    - Change size. rot90      - Rotate matrix 90 degrees. tril       - Extract lower triangular part. triu       - Extract upper triangular part. :          - Index into matrix, rearrange matrix.

code

code >> help specmat

Specialized matrices.

compan     - Companion matrix. gallery    - Several small test matrices. hadamard   - Hadamard matrix. hankel     - Hankel matrix. hilb       - Hilbert matrix. invhilb    - Inverse Hilbert matrix. kron       - Kronecker tensor product. magic      - Magic square. pascal     - Pascal matrix. rosser     - Classic symmetric eigenvalue test problem. toeplitz   - Toeplitz matrix. vander     - Vandermonde matrix. wilkinson  - Wilkinson's eigenvalue test matrix.

code

code >> help elfun

Elementary math functions.

Trigonometric. sin        - Sine. sinh       - Hyperbolic sine. asin       - Inverse sine. asinh      - Inverse hyperbolic sine. cos        - Cosine. cosh       - Hyperbolic cosine. acos       - Inverse cosine. acosh      - Inverse hyperbolic cosine. tan        - Tangent. tanh       - Hyperbolic tangent. atan       - Inverse tangent. atan2      - Four quadrant inverse tangent. atanh      - Inverse hyperbolic tangent. sec        - Secant. sech       - Hyperbolic secant. asec       - Inverse secant. asech      - Inverse hyperbolic secant. csc        - Cosecant. csch       - Hyperbolic cosecant. acsc       - Inverse cosecant. acsch      - Inverse hyperbolic cosecant. cot        - Cotangent. coth       - Hyperbolic cotangent. acot       - Inverse cotangent. acoth      - Inverse hyperbolic cotangent.

Exponential. exp        - Exponential. log        - Natural logarithm. log10      - Common logarithm. sqrt       - Square root.

Complex. abs        - Absolute value. angle      - Phase angle. conj       - Complex conjugate. imag       - Complex imaginary part. real       - Complex real part.

Numeric. fix        - Round towards zero. floor      - Round towards minus infinity. ceil       - Round towards plus infinity. round      - Round towards nearest integer. rem        - Remainder after division. sign       - Signum function.

code

code >> help specfun

Specialized math functions.

besselj    - Bessel function of the first kind. bessely    - Bessel function of the second kind. besseli    - Modified Bessel function of the first kind. besselk    - Modified Bessel function of the second kind. beta       - Beta function. betainc    - Incomplete beta function. betaln     - Logarithm of beta function. ellipj     - Jacobi elliptic functions. ellipke    - Complete elliptic integral. erf        - Error function. erfc       - Complementary error function. erfcx      - Scaled complementary error function. erfinv     - Inverse error function. expint     - Exponential integral function. gamma      - Gamma function. gcd        - Greatest common divisor. gammainc   - Incomplete gamma function. lcm        - Least common multiple. legendre   - Associated Legendre function. gammaln    - Logarithm of gamma function. log2       - Dissect floating point numbers. pow2       - Scale floating point numbers. rat        - Rational approximation. rats       - Rational output. cart2sph   - Transform from Cartesian to spherical coordinates. cart2pol   - Transform from Cartesian to polar coordinates. pol2cart   - Transform from polar to Cartesian coordinates. sph2cart   - Transform from spherical to Cartesian coordinates.

code

code >> help matfun

Matrix functions - numerical linear algebra.

Matrix analysis. cond       - Matrix condition number. norm       - Matrix or vector norm. rcond      - LINPACK reciprocal condition estimator. rank       - Number of linearly independent rows or columns. det        - Determinant. trace      - Sum of diagonal elements. null       - Null space. orth       - Orthogonalization. rref       - Reduced row echelon form.

Linear equations. \ and /    - Linear equation solution; use "help slash". chol       - Cholesky factorization. lu         - Factors from Gaussian elimination. inv        - Matrix inverse. qr         - Orthogonal-triangular decomposition. qrdelete   - Delete a column from the QR factorization. qrinsert   - Insert a column in the QR factorization. nnls       - Non-negative least-squares. pinv       - Pseudoinverse. lscov      - Least squares in the presence of known covariance.

Eigenvalues and singular values. eig        - Eigenvalues and eigenvectors. poly       - Characteristic polynomial. polyeig    - Polynomial eigenvalue problem. hess       - Hessenberg form. qz         - Generalized eigenvalues. rsf2csf    - Real block diagonal form to complex diagonal form. cdf2rdf    - Complex diagonal form to real block diagonal form. schur      - Schur decomposition. balance    - Diagonal scaling to improve eigenvalue accuracy. svd        - Singular value decomposition.

Matrix functions. expm       - Matrix exponential. expm1      - M-file implementation of expm. expm2      - Matrix exponential via Taylor series. expm3      - Matrix exponential via eigenvalues and eigenvectors. logm       - Matrix logarithm. sqrtm      - Matrix square root. funm       - Evaluate general matrix function.

code

code >> help general

General purpose commands. MATLAB Toolbox Version 4.2a 25-Jul-94

Managing commands and functions. help       - On-line documentation. doc        - Load hypertext documentation. what       - Directory listing of M-, MAT- and MEX-files. type       - List M-file. lookfor    - Keyword search through the HELP entries. which      - Locate functions and files. demo       - Run demos. path       - Control MATLAB's search path.

Managing variables and the workspace. who        - List current variables. whos       - List current variables, long form. load       - Retrieve variables from disk. save       - Save workspace variables to disk. clear      - Clear variables and functions from memory. pack       - Consolidate workspace memory. size       - Size of matrix. length     - Length of vector. disp       - Display matrix or text.

Working with files and the operating system. cd         - Change current working directory. dir        - Directory listing. delete     - Delete file. getenv     - Get environment value. !          - Execute operating system command. unix       - Execute operating system command & return result. diary      - Save text of MATLAB session.

Controlling the command window. cedit      - Set command line edit/recall facility parameters. clc        - Clear command window. home       - Send cursor home. format     - Set output format. echo       - Echo commands inside script files. more       - Control paged output in command window.

Starting and quitting from MATLAB. quit       - Terminate MATLAB. startup    - M-file executed when MATLAB is invoked. matlabrc   - Master startup M-file.

General information. info       - Information about MATLAB and The MathWorks, Inc. subscribe  - Become subscribing user of MATLAB. hostid     - MATLAB server host identification number. whatsnew   - Information about new features not yet documented. ver        - MATLAB, SIMULINK, and TOOLBOX version information.

code

code >> help funfun

Function functions - nonlinear numerical methods.

ode23      - Solve differential equations, low order method. ode23p     - Solve and plot solutions. ode45      - Solve differential equations, high order method. quad       - Numerically evaluate integral, low order method. quad8      - Numerically evaluate integral, high order method. fmin       - Minimize function of one variable. fmins      - Minimize function of several variables. fzero      - Find zero of function of one variable. fplot      - Plot function.

See also The Optimization Toolbox, which has a comprehensive set of function functions for optimizing and minimizing functions.

code

code >> help polyfun

Polynomial and interpolation functions.

Polynomials. roots      - Find polynomial roots. poly       - Construct polynomial with specified roots. polyval    - Evaluate polynomial. polyvalm   - Evaluate polynomial with matrix argument. residue    - Partial-fraction expansion (residues). polyfit    - Fit polynomial to data. polyder    - Differentiate polynomial. conv       - Multiply polynomials. deconv     - Divide polynomials.

Data interpolation. interp1    - 1-D interpolation (1-D table lookup). interp2    - 2-D interpolation (2-D table lookup). interpft   - 1-D interpolation using FFT method. griddata   - Data gridding.

Spline interpolation. spline     - Cubic spline data interpolation. ppval      - Evaluate piecewise polynomial.

code

code >> help ops

Operators and special characters.

Char   Name                         HELP topic

+     Plus                         arith -     Minus                        arith *     Matrix multiplication        arith .*    Array multiplication         arith ^     Matrix power                 arith .^    Array power                  arith

\     Backslash or left division   slash /     Slash or right division      slash ./    Array division               slash kron  Kronecker tensor product     kron



Parentheses                 paren [ ]   Brackets                     paren

.     Decimal point                punct ..    Parent directory             punct ...   Continuation                 punct ,     Comma                        punct ;     Semicolon                    punct %     Comment                      punct !     Exclamation point            punct '     Transpose and quote          punct =     Assignment                   punct

==    Equality                     relop <,>   Relational operators         relop &     Logical AND                  relop |     Logical OR                   relop ~     Logical NOT                  relop xor   Logical EXCLUSIVE OR         xor

Logical characteristics. exist      - Check if variables or functions are defined. any        - True if any element of vector is true. all        - True if all elements of vector are true. find       - Find indices of non-zero elements. isnan      - True for Not-A-Number. isinf      - True for infinite elements. finite     - True for finite elements. isempty    - True for empty matrix. isreal     - True for real matrix. issparse   - True for sparse matrix. isstr      - True for text string. isglobal   - True for global variables.

code

code >> help lang

Language constructs and debugging.

MATLAB as a programming language. script     - About MATLAB scripts and M-files. function   - Add new function. eval       - Execute string with MATLAB expression. feval      - Execute function specified by string. global     - Define global variable. nargchk    - Validate number of input arguments. lasterr    - Last error message.

Control flow. if         - Conditionally execute statements. else       - Used with IF. elseif     - Used with IF. end        - Terminate the scope of FOR, WHILE and IF statements. for        - Repeat statements a specific number of times. while      - Repeat statements an indefinite number of times. break      - Terminate execution of loop. return     - Return to invoking function. error      - Display message and abort function.

Interactive input. input      - Prompt for user input. keyboard   - Invoke keyboard as if it were a Script-file. menu       - Generate menu of choices for user input. pause      - Wait for user response. uimenu     - Create user interface menu. uicontrol  - Create user interface control.

Debugging commands. dbstop    - Set breakpoint. dbclear   - Remove breakpoint. dbcont    - Resume execution. dbdown    - Change local workspace context. dbstack   - List who called whom. dbstatus  - List all breakpoints. dbstep    - Execute one or more lines. dbtype    - List M-file with line numbers. dbup      - Change local workspace context. dbquit    - Quit debug mode. mexdebug  - Debug MEX-files.

code

code >> help plotxy Two dimensional graphics.

Elementary X-Y graphs. plot     - Linear plot. loglog   - Log-log scale plot. semilogx - Semi-log scale plot. semilogy - Semi-log scale plot. fill     - Draw filled 2-D polygons.

Specialized X-Y graphs. polar    - Polar coordinate plot. bar      - Bar graph. stem     - Discrete sequence or "stem" plot. stairs   - Stairstep plot. errorbar - Error bar plot. hist     - Histogram plot. rose     - Angle histogram plot. compass  - Compass plot. feather  - Feather plot. fplot    - Plot function. comet    - Comet-like trajectory.

Graph annotation. title    - Graph title. xlabel   - X-axis label. ylabel   - Y-axis label. text     - Text annotation. gtext    - Mouse placement of text. grid     - Grid lines.

See also PLOTXYZ, GRAPHICS.

code

code >> help plotxyz

Three dimensional graphics.

Line and area fill commands. plot3     - Plot lines and points in 3-D space. fill3     - Draw filled 3-D polygons in 3-D space. comet3    - 3-D comet-like trajectories.

Contour and other 2-D plots of 3-D data. contour   - Contour plot. contour3  - 3-D contour plot. clabel    - Contour plot elevation labels. contourc  - Contour plot computation (used by contour). pcolor    - Pseudocolor (checkerboard) plot. quiver    - Quiver plot.

Surface and mesh plots. mesh      - 3-D mesh surface. meshc     - Combination mesh/contour plot. meshz     - 3-D Mesh with zero plane. surf      - 3-D shaded surface. surfc     - Combination surf/contour plot. surfl     - 3-D shaded surface with lighting. waterfall - Waterfall plot.

Volume visualization. slice     - Volumetric visualization plots.

Graph appearance. view      - 3-D graph viewpoint specification. viewmtx   - View transformation matrices. hidden    - Mesh hidden line removal mode. shading   - Color shading mode. axis      - Axis scaling and appearance. caxis     - Pseudocolor axis scaling. colormap  - Color look-up table.

Graph annotation. title     - Graph title. xlabel    - X-axis label. ylabel    - Y-axis label. zlabel    - Z-axis label for 3-D plots. text      - Text annotation. gtext     - Mouse placement of text. grid      - Grid lines.

3-D objects. cylinder  - Generate cylinder. sphere    - Generate sphere.

See also COLOR, PLOTXY, GRAPHICS.

code

code >> help strfun

Character string functions.

General. strings    - About character strings in MATLAB. abs        - Convert string to numeric values. setstr     - Convert numeric values to string. isstr      - True for string. blanks     - String of blanks. deblank    - Remove trailing blanks. str2mat    - Form text matrix from individual strings. eval       - Execute string with MATLAB expression.

String comparison. strcmp     - Compare strings. findstr    - Find one string within another. upper      - Convert string to uppercase. lower      - Convert string to lowercase. isletter   - True for letters of the alphabet. isspace    - True for white space characters. strrep     - Replace a string with another. strtok     - Find a token in a string.

String to number conversion. num2str    - Convert number to string. int2str    - Convert integer to string. str2num    - Convert string to number. mat2str    - Convert matrix to string. sprintf    - Convert number to string under format control. sscanf     - Convert string to number under format control.

Hexadecimal to number conversion. hex2num    - Convert hex string to IEEE floating point number. hex2dec    - Convert hex string to decimal integer. dec2hex    - Convert decimal integer to hex string. code