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Annotation of OpenXM/src/R/r-packages/hgm/man/hgm.cwishart.Rd, Revision 1.13

1.13    ! takayama    1: % $OpenXM: OpenXM/src/R/r-packages/hgm/man/hgm.cwishart.Rd,v 1.12 2016/02/14 00:21:50 takayama Exp $
1.4       takayama    2: \name{hgm.pwishart}
                      3: \alias{hgm.pwishart}
1.1       takayama    4: %- Also NEED an '\alias' for EACH other topic documented here.
                      5: \title{
1.4       takayama    6:     The function hgm.pwishart evaluates the cumulative distribution function
1.7       takayama    7:   of random wishart matrices.
1.1       takayama    8: }
                      9: \description{
1.4       takayama   10:     The function hgm.pwishart evaluates the cumulative distribution function
1.7       takayama   11:   of random wishart matrices of size m times m.
1.1       takayama   12: }
                     13: \usage{
1.9       takayama   14: hgm.pwishart(m,n,beta,q0,approxdeg,h,dp,q,mode,method,
1.12      takayama   15:             err,automatic,assigned_series_error,verbose,autoplot)
1.1       takayama   16: }
                     17: %- maybe also 'usage' for other objects documented here.
                     18: \arguments{
1.2       takayama   19:   \item{m}{The dimension of the Wishart matrix.}
                     20:   \item{n}{The degree of freedome (a parameter of the Wishart distribution)}
1.3       takayama   21:   \item{beta}{The eigenvalues of the inverse of the covariant matrix /2
                     22: (a parameter of the Wishart distribution).
                     23:     The beta is equal to inverse(sigma)/2.
1.1       takayama   24:   }
1.4       takayama   25:   \item{q0}{The point to evaluate the matrix hypergeometric series. q0>0}
1.1       takayama   26:   \item{approxdeg}{
1.2       takayama   27:     Zonal polynomials upto the approxdeg are calculated to evaluate
                     28:    values near the origin. A zonal polynomial is determined by a given
                     29:    partition (k1,...,km). We call the sum k1+...+km the degree.
1.1       takayama   30:   }
                     31:   \item{h}{
1.2       takayama   32:    A (small) step size for the Runge-Kutta method. h>0.
1.1       takayama   33:   }
                     34:   \item{dp}{
1.2       takayama   35:     Sampling interval of solutions by the Runge-Kutta method.
1.12      takayama   36:     When autoplot=1, it is automatically set.
1.2       takayama   37:   }
1.4       takayama   38:   \item{q}{
                     39:     The second value y[0] of this function is the Prob(L1 < q)
1.2       takayama   40:     where L1 is the first eigenvalue of the Wishart matrix.
1.1       takayama   41:   }
1.3       takayama   42:   \item{mode}{
                     43:     When mode=c(1,0,0), it returns the evaluation
1.11      takayama   44:     of the matrix hypergeometric series and its derivatives at q0.
1.13    ! takayama   45:     When mode=c(1,1,(2^m+1)*p), intermediate values of P(L1 < x) with respect to
1.3       takayama   46:     p-steps of x are also returned.  Sampling interval is controled by dp.
1.12      takayama   47:     When autoplot=1, it is automatically set.
1.3       takayama   48:   }
                     49:   \item{method}{
1.5       takayama   50:     a-rk4 is the default value.
1.3       takayama   51:     When method="a-rk4", the adaptive Runge-Kutta method is used.
                     52:     Steps are automatically adjusted by err.
                     53:   }
                     54:   \item{err}{
                     55:     When err=c(e1,e2), e1 is the absolute error and e2 is the relative error.
1.13    ! takayama   56:     This parameter controls the adative Runge-Kutta method.
        !            57:     If the output is absurd, you may get a correct answer by setting,  e.g.,
        !            58:     err=c(1e-(xy+5), 1e-10) when initial value at q0 is very small as 1e-xy.
1.3       takayama   59:   }
1.5       takayama   60:   \item{automatic}{
                     61:     automatic=1 is the default value.
                     62:     If it is 1, the degree of the series approximation will be increased until
                     63:     |(F(i)-F(i-1))/F(i-1)| < assigned_series_error where
                     64:     F(i) is the degree i approximation of the hypergeometric series
                     65:     with matrix argument.
1.6       takayama   66:     Step sizes for the Runge-Kutta method are also set automatically from
                     67:     the assigned_series_error if it is 1.
1.5       takayama   68:   }
                     69:   \item{assigned_series_error}{
                     70:     assigned_series_error=0.00001 is the default value.
                     71:   }
                     72:   \item{verbose}{
                     73:     verbose=0 is the default value.
                     74:     If it is 1, then steps of automatic degree updates and several parameters
                     75:     are output to stdout and stderr.
                     76:   }
1.12      takayama   77:   \item{autoplot}{
                     78:     autoplot=0 is the default value.
                     79:     If it is 1, then it outputs an input for plot.
                     80:     When ans is the output, ans[1,] is c(q,prob at q,...), ans[2,] is c(q0,prob at q0,...), and ans[3,] is c(q0+q/100,prob at q/100,...), ...
                     81:   }
1.1       takayama   82: }
                     83: \details{
1.2       takayama   84:   It is evaluated by the Koev-Edelman algorithm when x is near the origin and
                     85:   by the HGM when x is far from the origin.
1.3       takayama   86:   We can obtain more accurate result when the variables h is smaller,
1.11      takayama   87:   q0 is relevant value (not very big, not very small),
1.2       takayama   88:   and the approxdeg is more larger.
1.11      takayama   89:   A heuristic method to set parameters q0, h, approxdeg properly
1.3       takayama   90:   is to make x larger and to check if the y[0] approaches to 1.
1.1       takayama   91: %  \code{\link[RCurl]{postForm}}.
                     92: }
                     93: \value{
1.3       takayama   94: The output is x, y[0], ..., y[2^m] in the default mode,
1.2       takayama   95: y[0] is the value of the cumulative distribution
                     96: function P(L1 < x) at x.  y[1],...,y[2^m] are some derivatives.
                     97: See the reference below.
1.1       takayama   98: }
                     99: \references{
1.2       takayama  100: H.Hashiguchi, Y.Numata, N.Takayama, A.Takemura,
1.6       takayama  101: Holonomic gradient method for the distribution function of the largest root of a Wishart matrix,
                    102: Journal of Multivariate Analysis, 117, (2013) 296-312,
                    103: \url{http://dx.doi.org/10.1016/j.jmva.2013.03.011},
1.1       takayama  104: }
                    105: \author{
                    106: Nobuki Takayama
                    107: }
                    108: \note{
1.7       takayama  109: This function does not work well under the following cases:
                    110: 1. The beta (the set of eigenvalues)
                    111: is degenerated or is almost degenerated.
                    112: 2. The beta is very skew, in other words, there is a big eigenvalue
                    113: and there is also a small eigenvalue.
                    114: The error control is done by a heuristic method.
                    115: The obtained value is not validated automatically.
1.1       takayama  116: }
                    117:
                    118: %% ~Make other sections like Warning with \section{Warning }{....} ~
                    119:
1.10      takayama  120: %\seealso{
                    121: %%%\code{\link{oxm.matrix_r2tfb}}
                    122: %}
1.1       takayama  123: \examples{
                    124: ## =====================================================
1.3       takayama  125: ## Example 1.
1.1       takayama  126: ## =====================================================
1.4       takayama  127: hgm.pwishart(m=3,n=5,beta=c(1,2,3),q=10)
1.3       takayama  128: ## =====================================================
                    129: ## Example 2.
                    130: ## =====================================================
1.4       takayama  131: b<-hgm.pwishart(m=4,n=10,beta=c(1,2,3,4),q0=1,q=10,approxdeg=20,mode=c(1,1,(16+1)*100));
1.3       takayama  132: c<-matrix(b,ncol=16+1,byrow=1);
                    133: #plot(c)
1.12      takayama  134: ## =====================================================
                    135: ## Example 3.
                    136: ## =====================================================
                    137: c<-hgm.pwishart(m=4,n=10,beta=c(1,2,3,4),q0=1,q=10,approxdeg=20,autoplot=1);
                    138: #plot(c)
1.1       takayama  139: }
                    140: % Add one or more standard keywords, see file 'KEYWORDS' in the
                    141: % R documentation directory.
                    142: \keyword{ Cumulative distribution function of random wishart matrix }
                    143: \keyword{ Holonomic gradient method }
                    144: \keyword{ HGM }
                    145:

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