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Class org.netlib.lapack.Dtptri

java.lang.Object
   |
   +----org.netlib.lapack.Dtptri

public class Dtptri

extends Object

Following is the description from the original
Fortran source.  For each array argument, the Java
version will include an integer offset parameter, so
the arguments may not match the description exactly.
Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  Purpose
 *  =======
 *
 *  DTPTRI computes the inverse of a real upper or lower triangular
 *  matrix A stored in packed format.
 *
 *  Arguments
 *  =========
 *
 *  UPLO    (input) CHARACTER*1
 *          = 'U':  A is upper triangular;
 *          = 'L':  A is lower triangular.
 *
 *  DIAG    (input) CHARACTER*1
 *          = 'N':  A is non-unit triangular;
 *          = 'U':  A is unit triangular.
 *
 *  N       (input) INTEGER
 *          The order of the matrix A.  N >= 0.
 *
 *  AP      (input/output) DOUBLE PRECISION array, dimension (N*(N+1)/2)
 *          On entry, the upper or lower triangular matrix A, stored
 *          columnwise in a linear array.  The j-th column of A is stored
 *          in the array AP as follows:
 *          if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
 *          if UPLO = 'L', AP(i + (j-1)*((2*n-j)/2) = A(i,j) for j<=i<=n.
 *          See below for further details.
 *          On exit, the (triangular) inverse of the original matrix, in
 *          the same packed storage format.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *          > 0:  if INFO = i, A(i,i) is exactly zero.  The triangular
 *                matrix is singular and its inverse can not be computed.
 *
 *  Further Details
 *  ===============
 *
 *  A triangular matrix A can be transferred to packed storage using one
 *  of the following program segments:
 *
 *  UPLO = 'U':                      UPLO = 'L':
 *
 *        JC = 1                           JC = 1
 *        DO 2 J = 1, N                    DO 2 J = 1, N
 *           DO 1 I = 1, J                    DO 1 I = J, N
 *              AP(JC+I-1) = A(I,J)              AP(JC+I-J) = A(I,J)
 *      1    CONTINUE                    1    CONTINUE
 *           JC = JC + J                      JC = JC + N - J + 1
 *      2 CONTINUE                       2 CONTINUE
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Dtptri()

dtptri(String, String, int, double[], int, intW)

 public Dtptri()

 public static void dtptri(String uplo,
                           String diag,
                           int n,
                           double ap[],
                           int _ap_offset,
                           intW info)

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