short-reference.mht 1/ /WK/

Transcription

1 short-reference.mht 1/6 6KRUW0$7/$%5HIHUHQFH There are many MATLAB features which cannot be included in these introductory notes. Listed below are some of the MATLAB functions and operators available, grouped by subject area (Source: MATLAB User s Guide, version 3.5). Use the on-line help facility or consult the User s Guide for more detailed information on the functions. There are many functions beyond these. There exist, in particular, several "toolboxes" of functions for specific areas; included among such are signal processing, control systems, robust-control, system identification, optimization, splines, chemometrics, mu-analysis and synthesis, state-space identification, and neural networks. (The toolboxes, which are optional, may not be installed on your system.) These can be explored via the command help. *HQHUDO help help facility demo run demonstrations who list variables in memory what list M-files on disk size row and column dimensions length vector length clear clear workspace computer type of computer ^C local abort exit exit MATLAB quit same as exit 0DWUL[$UUD\2SHUDWRUV Matrix Operators Array Operators addition + addition - subtraction - subtraction * multiplication.* multiplication / right division./ right division \ left division.\ left division ^ power.^ power conjugate transpose. transpose 5HODWLRQDODQG/RJLFDO2SHUDWRUV < less than <= less than or equal > greater than >= greater than or equal == equal ~= not equal & and or ~ not 6SHFLDO&KDUDFWHUV = assignment statement [ used to form vectors and matrices ] see [

2 short-reference.mht 2/6 ( arithmetic expression precedence ) see (. decimal point... continue statement to next line, separate subscripts and function arguments ; end rows, suppress printing % comments : subscripting, vector generation! execute operating system command 6SHFLDO9DOXHV ans answer when expression not assigned eps floating point precision pi pi i, j sqrt(-1) inf infinity NaN Not-a-Number clock wall clock date date flops floating point operation count nargin number of function input arguments nargout number of function output arguments 'LVN)LOHV chdir delete diary dir load save type what fprintf pack change current directory delete file diary of the session directory of files on disk load variables from file save variables to file list function or file show M-files on disk write to a file compact memory via VDYH 6SHFLDO0DWULFHV compan companion diag diagonal eye identity gallery esoteric hadamard Hadamard hankel Hankel hilb Hilbert invhilb inverse Hilbert linspace linearly spaced vectors logspace logarithmically spaced vectors magic magic square meshdom domain for mesh points ones constant pascal Pascal rand random elements toeplitz Toeplitz vander Vandermonde zeros zero 0DWUL[0DQLSXODWLRQ

3 short-reference.mht 3/6 rot90 rotation fliplr flip matrix left-to-right flipud flip matrix up-to-down diag diagonal matrices tril lower triangular part triu upper triangular part reshape reshape. transpose : convert matrix to single column; A(:) 5HODWLRQDODQG/RJLFDO)XQFWLRQV any all find isnan finite isempty isstr strcmp logical conditions logical conditions find array indices of logical values detect NaNs detect infinities detect empty matrices detect string variables compare string variables &RQWURO)ORZ if elseif else end for while break return pause conditionally execute statements used with LI used with LI terminate ELIIRUZKLOH repeat statements a number of times do while break out of IRU and ZKLOH loops return from functions pause until key pressed 3URJUDPPLQJDQG0ILOHV input get numbers from keyboard keyboard call keyboard as M-file error display error message function define function eval interpret text in variables feval evaluate function given by string echo enable command echoing exist check if variables exist casesen set case sensitivity global define global variables startup startup M-file getenv get environment string menu select item from menu etime elapsed time 7H[WDQG6WULQJV abs eval num2str int2str setstr sprintf convert string to ASCII values evaluate text macro convert number to string convert integer to string set flag indicating matrix is a string convert number to string

4 short-reference.mht 4/6 isstr strcomp hex2num detect string variables compare string variables convert hex string to number &RPPDQG:LQGRZ clc home format disp fprintf echo clear command screen move cursor home set output display format display matrix or text print formatted number enable command echoing *UDSK3DSHU plot linear X-Y plot loglog loglog X-Y plot semilogx semi-log X-Y plot semilogy semi-log X-Y plot polar polar plot mesh 3-dimensional mesh surface contour contour plot meshdom domain for mesh plots bar bar charts stairs stairstep graph errorbar add error bars *UDSK$QQRWDWLRQ title xlabel ylabel grid text gtext ginput plot title x-axis label y-axis label draw grid lines arbitrarily position text mouse-positioned text graphics input *UDSK:LQGRZ&RQWURO axis hold shg clg subplot manual axis scaling hold plot on screen show graph window clear graph window split graph window *UDSK:LQGRZ+DUGFRS\ print prtsc meta send graph to printer screen dump graphics metafile (OHPHQWDU\0DWK)XQFWLRQV abs angle sqrt real absolute value or complex magnitude phase angle square root real part

5 short-reference.mht 5/6 imag imaginary part conj complex conjugate round round to nearest integer fix round toward zero floor round toward -infinity ceil round toward infinity sign signum function rem remainder exp exponential base e log natural logarithm log10 log base 10 7ULJRQRPHWULF)XQFWLRQV sin cos tan asin acos atan atan2 sinh cosh tanh asinh acosh atanh sine cosine tangent arcsine arccosine arctangent four quadrant arctangent hyperbolic sine hyperbolic cosine hyperbolic tangent hyperbolic arcsine hyperbolic arccosine hyperbolic arctangent 'HFRPSRVLWLRQVDQG)DFWRUL]DWLRQV balance backsub cdf2rdf chol eig hess inv lu nnls null orth pinv qr qz rref schur svd balanced form backsubstitution convert complex-diagonal to real-diagonal Cholesky factorization eigenvalues and eigenvectors Hessenberg form inverse factors from Gaussian elimination nonnegative least squares null space orthogonalization pseudoinverse orthogonal-triangular decomposition QZ algorithm reduced row echelon form Schur decomposition singular value decomposition (OHPHQWDU\0DWUL[)XQFWLRQV expm logm sqrtm funm poly det trace kron matrix exponential matrix logarithm matrix square root arbitrary matrix function characteristic polynomial determinant trace Kronecker tensor product

6 short-reference.mht 6/6 &ROXPQZLVH'DWD$QDO\VLV max maximum value min minimum value mean mean value median median value std standard deviation sort sorting sum sum of elements prod product of elements cumsum cumulative sum of elements cumprod cumulative product of elements diff approximate derivatives hist histograms corrcoef correlation coefficients cov covariance matrix cplxpair reorder into complex pairs 6LJQDO3URFHVVLQJ abs complex magnitude angle phase angle conv convolution corrcoef correlation coefficients cov covariance deconv deconvolution fft radix-2 fast Fourier transform fft2 two-dimensional FFT ifft inverse fast Fourier transform ifft2 inverse 2-D FFT fftshift FFT rearrangement 1RQOLQHDU(TXDWLRQVDQG2SWLPL]DWLRQ fmin fmins fsolve fzero minimum of a function of one variable minimum of a multivariable function solution of a system of nonlinear equations (zeros of a multivariable function) zero of a function of one variable,qwhusrodwlrq spline table1 table2 cubic spline 1-D table look-up 2-D table look-up