On This Page Math Language Function Reference On the Web Articles Forum Knowledge Center Technical Support Training Math Language Function Reference To go directly to entries that start with a specific letter, select one of the following: A, B, C, D, E, F, G, H, I, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Z. Function Name Description abs absolute value or magnitude acos inverse cosine, in radians acosd inverse cosine, in degrees acosh inverse hyperbolic cosine acot inverse cotangent acotd inverse cotangent, in degrees acoth inverse hyperbolic cotangent acsc inverse cosecant acscd inverse cosecant, in degrees acsch inverse hyperbolic cosecant all true if all elements in a vector are nonzero angle phase of a complex number, in radians any true if any element in a vector is nonzero asecd inverse secant, in degrees asech inverse hyperbolic secant asin inverse sine, in radians asind inverse sine, in degrees asinh inverse hyperbolic sine atan inverse tangent, in radians atan2 4-quadrant inverse tangent, in radians atand inverse tangent, in degrees atanh inverse hyperbolic tangent bartlett Bartlett Window blackman Blackman Window butter Butterworth filter designer ceil smallest integer greater than or equal to argument cell create a cell array cheby1 Chebyshev type 1 filter designer cheby2 Chebyshev type 2 filter designer class data-type (class name) of argument clc clear the command window clear delete a class object conj complex conjugate conv linear convolution (or polynomial multiplication) cos cosine of a radian-valued argument cosd cosine of a degree-valued argument cosh hyperbolic cosine cot cotangent of a radian-valued argument cotd cotangent of a degree-valued argument coth hyperbolic cotangent csc cosecant of a radian-valued argument cscd cosecant of a degree-valued argument csch hyperbolic cosecant cumprod cumulative product of elements of a vector cumsum cumulative sum of elements of a vector dbg_print output to equation debug window dbg_showvar output contents of a variable to equation debug window deconv deconvolution (or polynomial division) diag create diagonal matrix or extract diagonal of a matrix diff difference (or approximate derivative) eig eigenvalues and eigenvectors of a matrix ellip Elliptic or Cauer filter designer eps spacing of floating point numbers erf error function erfc complementary error function error posts to error log or output error to command window exp exponential eye construct identity matrix false logical false fclose close a file or stream fft Discrete Fourier Transform (DFT) fftshift shift zero-frequency to center of spectrum fgetl read a line from a file, discard newline fgets read a line from a file, keep newline filter one dimensional digital filtering find indices of nonzero elements fir1 FIR filter design using window method fix round toward zero flipdim flip matrix along a dimension fliplr left/right matrix flip flipud up/down matrix flip floor largest integer less than or equal to argument fopen open file or stream fread read binary data from a file or stream fprintf write formatted text to a file or stream fscanf read formatted text from a file or stream fwrite write binary data to a file or stream gausswin Gaussian Window getvariable get the value of a variable from a dataset hamming Hamming Window hann Hann Window hankel construct Hankel matrix histc histogram count ifft Inverse Discrete Fourier Transform (IDFT) ifftshift inverse FFT shift imag imaginary part of a complex number inf infinity interp1 one dimensional interpolation ipermute inverse permutation of array dimensions iscell true if argument is a cell array ischar true if argument is of type character array isempty true if argument is empty or array with a dimension of length 0 isequal true if arrays contain equal values, ignoring NaNs isequalwithequalnans true if arrays contain equal values, including NaNs isfield true if a field is in a structure or structure array isfinite true for finite elements isfloat true if argument is a floating point scalar or array isinf true for infinite elements isinteger true if argument is an integer scalar or array islogical true if argument is a logical scalar or array isnan true for NaN elements isnumeric true if argument is a numeric scalar or array isreal true if argument is a real-valued scalar or array isscalar true if argument is a scalar isstr true if argument is a character array isstruct true if argument is a structure array isvector true if argument is a vector kurtosis sample kurtosis length length of a vector linspace construct linearly spaced vector log natural logarithm log2 Base-2 logarithm log10 Base-10 logarithm logspace construct logarithmically spaced vector lookup look up values in a sorted table max largest value of a vector mean arithmetic mean of a vector median median of a vector min smallest value of a vector mkpp construct a piecewise polynomial mod modulus after division mode mode (most frequent value) of a vector moment nth order central moment of a vector nan Not-a-Number ndims number of dimensions of the argument num2str convert number to a character array numel total number of elements in an array ones construct array with elements set to 1 pchip construct piecewise cubic Hermite interpolating polynomial permute permutation of array dimensions poly convert roots to a polynomial polyval evaluate a polynomial polyvalm evaluate a polynomial with a matrix argument ppval evaluate a piecewise polynomial prctile p'th percentiles of a vector prod product of elements of a vector quantile q'th quantiles of a vector rand uniformly distributed random numbers between 0 and 1 randn Normally (Gaussian) distributed random numbers real real part of a complex number rectwin Rectangular Window rem remainder after division repmat replicate and tile an array reshape change dimensions of an array roots roots of a polynomial rot90 rotate a matrix 90 degrees round round towards nearest integer sec secant of a radian-valued argument secd secant of a degree-valued argument sech hyperbolic secant setvariable write a value to a variable in a dataset shiftdim shift array dimensions sign signum sin sine of a radian-valued argument sinc sinc function (sin(pi*x) / (pi*x)) sind sine of a degree-valued argument sinh hyperbolic sine size dimensions of an array skewness skewness of a vector sort sort a vector in ascending or descending order spline cubic spline interpolation sqrt square root std standard deviation of a vector str2num convert a string to a number strcmp case-sensitive string comparison strcmpi case-insensitive string comparison strncmp compare first N characters of a string (case-sensitive) strncmpi compare first N characters of a string (case-insensitive) struct construct a structure array sum sum of the elements of a vector tan tangent of a radian-valued argument tand tangent of a degree-valued argument tanh hyperbolic tangent tcpip construct tcpip stream object for TCP/IP communications toeplitz construct Toeplitz matrix true logical true unmkpp details of piecewise polynomial var variance of a vector warning posts a warning to error log or output warning to command window xor logical exclusive-OR zeros construct array with elements set to 0