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Annotation of OpenXM/src/R/r-packages/hgm/man/hgm.c2wishart.Rd, Revision 1.1

1.1     ! takayama    1: % $OpenXM$
        !             2: \name{hgm.p2wishart}
        !             3: \alias{hgm.p2wishart}
        !             4: %- Also NEED an '\alias' for EACH other topic documented here.
        !             5: \title{
        !             6:     The function hgm.p2wishart evaluates the cumulative distribution function
        !             7:   of the largest eigenvalues of inverse(S2)*S1.
        !             8: }
        !             9: \description{
        !            10:     The function hgm.p2wishart evaluates the cumulative distribution function
        !            11:   of the largest eigenvalues of W1*inverse(W2) where W1 and W2 are Wishart
        !            12:   matrices of size m*m of the freedom n1 and n2 respectively.
        !            13: }
        !            14: \usage{
        !            15: hgm.p2wishart(m,n1,n2,beta,q0,approxdeg,h,dp,q,mode,method,
        !            16:             err,automatic,assigned_series_error,verbose)
        !            17: }
        !            18: %- maybe also 'usage' for other objects documented here.
        !            19: \arguments{
        !            20:   \item{m}{The dimension of the Wishart matrix.}
        !            21:   \item{n1}{The degree of freedome of the Wishart distribution S1}
        !            22:   \item{n2}{The degree of freedome of the Wishart distribution S2}
        !            23:   \item{beta}{The eigenvalues of inverse(S2)*S1 where S1 and S2 are
        !            24:     covariant matrices of W1 and W2 respectively.
        !            25:   }
        !            26:   \item{q0}{The point to evaluate the matrix hypergeometric series. q0>0}
        !            27:   \item{approxdeg}{
        !            28:     Zonal polynomials upto the approxdeg are calculated to evaluate
        !            29:    values near the origin. A zonal polynomial is determined by a given
        !            30:    partition (k1,...,km). We call the sum k1+...+km the degree.
        !            31:   }
        !            32:   \item{h}{
        !            33:    A (small) step size for the Runge-Kutta method. h>0.
        !            34:   }
        !            35:   \item{dp}{
        !            36:     Sampling interval of solutions by the Runge-Kutta method.
        !            37:   }
        !            38:   \item{q}{
        !            39:     The second value y[0] of this function is the Prob(L1 < q)
        !            40:     where L1 is the first eigenvalue of the Wishart matrix.
        !            41:   }
        !            42:   \item{mode}{
        !            43:     When mode=c(1,0,0), it returns the evaluation
        !            44:     of the matrix hypergeometric series and its derivatives at x0.
        !            45:     When mode=c(1,1,(m^2+1)*p), intermediate values of P(L1 < x) with respect to
        !            46:     p-steps of x are also returned.  Sampling interval is controled by dp.
        !            47:   }
        !            48:   \item{method}{
        !            49:     a-rk4 is the default value.
        !            50:     When method="a-rk4", the adaptive Runge-Kutta method is used.
        !            51:     Steps are automatically adjusted by err.
        !            52:   }
        !            53:   \item{err}{
        !            54:     When err=c(e1,e2), e1 is the absolute error and e2 is the relative error.
        !            55:     As long as NaN is not returned, it is recommended to set to
        !            56:     err=c(0.0, 1e-10), because initial values are usually very small.
        !            57:   }
        !            58:   \item{automatic}{
        !            59:     automatic=1 is the default value.
        !            60:     If it is 1, the degree of the series approximation will be increased until
        !            61:     |(F(i)-F(i-1))/F(i-1)| < assigned_series_error where
        !            62:     F(i) is the degree i approximation of the hypergeometric series
        !            63:     with matrix argument.
        !            64:     Step sizes for the Runge-Kutta method are also set automatically from
        !            65:     the assigned_series_error if it is 1.
        !            66:   }
        !            67:   \item{assigned_series_error}{
        !            68:     assigned_series_error=0.00001 is the default value.
        !            69:   }
        !            70:   \item{verbose}{
        !            71:     verbose=0 is the default value.
        !            72:     If it is 1, then steps of automatic degree updates and several parameters
        !            73:     are output to stdout and stderr.
        !            74:   }
        !            75: }
        !            76: \details{
        !            77:   It is evaluated by the Koev-Edelman algorithm when x is near the origin and
        !            78:   by the HGM when x is far from the origin.
        !            79:   We can obtain more accurate result when the variables h is smaller,
        !            80:   x0 is relevant value (not very big, not very small),
        !            81:   and the approxdeg is more larger.
        !            82:   A heuristic method to set parameters x0, h, approxdeg properly
        !            83:   is to make x larger and to check if the y[0] approaches to 1.
        !            84: %  \code{\link[RCurl]{postForm}}.
        !            85: }
        !            86: \value{
        !            87: The output is x, y[0], ..., y[2^m] in the default mode,
        !            88: y[0] is the value of the cumulative distribution
        !            89: function P(L1 < x) at x.  y[1],...,y[2^m] are some derivatives.
        !            90: See the reference below.
        !            91: }
        !            92: \references{
        !            93: H.Hashiguchi, N.Takayama, A.Takemura,
        !            94: in preparation.
        !            95: }
        !            96: \author{
        !            97: Nobuki Takayama
        !            98: }
        !            99: \note{
        !           100: This function does not work well under the following cases:
        !           101: 1. The beta (the set of eigenvalues)
        !           102: is degenerated or is almost degenerated.
        !           103: 2. The beta is very skew, in other words, there is a big eigenvalue
        !           104: and there is also a small eigenvalue.
        !           105: The error control is done by a heuristic method.
        !           106: The obtained value is not validated automatically.
        !           107: }
        !           108:
        !           109: %% ~Make other sections like Warning with \section{Warning }{....} ~
        !           110:
        !           111: %\seealso{
        !           112: %%%\code{\link{oxm.matrix_r2tfb}}
        !           113: %}
        !           114: \examples{
        !           115: ## =====================================================
        !           116: ## Example 1.
        !           117: ## =====================================================
        !           118: hgm.p2wishart(m=3,n1=5,n2=10,beta=c(1,2,4),q=4)
        !           119: ## =====================================================
        !           120: ## Example 2.
        !           121: ## =====================================================
        !           122: b<-hgm.p2wishart(m=3,n1=5,n2=10,beta=c(1,2,4),q0=0.1,q=20,approxdeg=20,mode=c(1,1,(8+1)*100));
        !           123: c<-matrix(b,ncol=16+1,byrow=1);
        !           124: #plot(c)
        !           125: }
        !           126: % Add one or more standard keywords, see file 'KEYWORDS' in the
        !           127: % R documentation directory.
        !           128: \keyword{ Cumulative distribution function of random two wishart matrices }
        !           129: \keyword{ Holonomic gradient method }
        !           130: \keyword{ HGM }
        !           131:

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