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Research/Etc_Research

Matlab Integral 명령어

QUAD   Numerically evaluate integral, adaptive Simpson quadrature.
    Q = QUAD(FUN,A,B) tries to approximate the integral of function
    FUN from A to B to within an error of 1.e-6 using recursive
    adaptive Simpson quadrature.  The function Y = FUN(X) should
    accept a vector argument X and return a vector result Y, the
    integrand evaluated at each element of X. 
 
    Q = QUAD(FUN,A,B,TOL) uses an absolute error tolerance of TOL
    instead of the default, which is 1.e-6.  Larger values of TOL
    result in fewer function evaluations and faster computation,
    but less accurate results.  The QUAD function in MATLAB 5.3 used
    a less reliable algorithm and a default tolerance of 1.e-3.
 
    [Q,FCNT] = QUAD(...) returns the number of function evaluations.
 
    QUAD(FUN,A,B,TOL,TRACE) with non-zero TRACE shows the values
    of [fcnt a b-a Q] during the recursion.
 
    QUAD(FUN,A,B,TOL,TRACE,P1,P2,...) provides for additional
    arguments P1, P2, ... to be passed directly to function FUN,
    FUN(X,P1,P2,...).  Pass empty matrices for TOL or TRACE to
    use the default values.
 
    Use array operators .*, ./ and .^ in the definition of FUN
    so that it can be evaluated with a vector argument.
 
    Function QUADL may be more efficient with high accuracies
    and smooth integrands.
 
    Example:
        FUN can be specified as:
 
        An anonymous function:
           F = @(x) 1./(x.^3-2*x-5);
           Q = quad(F,0,2);
 

        A function handle:
           Q = quad(@myfun,0,2);
           where myfun.m is an M-file:
              function y = myfun(x)
              y = 1./(x.^3-2*x-5);
 
    Class support for inputs A, B, and the output of FUN:
       float: double, single
 
    See also quadv, quadl, dblquad, triplequad, @, trapz.


    Reference page in Help browser
       doc quad

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