This class contains Java versions of a number of the LINPACK
basic linear algebra subroutines (blas):
isamax_f77
daxpy_f77
ddot_f77
dscal_f77
dswap_f77
dnrm2_f77
dcopy_f77
drotg_f77
It also contains utility routines that the translator found useful
while translating the FORTRAN code to Java code.
The chlhsn_f77 method finds
"THE L(L-TRANSPOSE) [WRITTEN LL+] DECOMPOSITION OF THE PERTURBED
MODEL HESSIAN MATRIX A+MU*I(WHERE MU\0 AND I IS THE IDENTITY MATRIX)
WHICH IS SAFELY POSITIVE DEFINITE.
The choldc_f77 method finds
"THE PERTURBED L(L-TRANSPOSE) [WRITTEN LL+] DECOMPOSITION
OF A+D, WHERE D IS A NON-NEGATIVE DIAGONAL MATRIX ADDED TO A IF
NECESSARY TO ALLOW THE CHOLESKY DECOMPOSITION TO CONTINUE."
Translated by Steve Verrill, April 15, 1998.
This method multiplies a constant times a portion of a column
of a matrix and adds the product to the corresponding portion
of another column of the matrix --- a portion of col2 is
replaced by the corresponding portion of a*col1 + col2.
This method multiplies a constant times a portion of a column
of a matrix x[ ][ ] and adds the product to the corresponding portion
of a vector y[ ] --- a portion of y[ ] is replaced by the corresponding
portion of ax[ ][j] + y[ ].
This method multiplies a constant times a portion of a vector y[ ]
and adds the product to the corresponding portion
of a column of a matrix x[ ][ ] --- a portion of column j of x[ ][ ]
is replaced by the corresponding
portion of ay[ ] + x[ ][j].
The fdjac2 method computes a forward-difference approximation
to the m by n Jacobian matrix associated with a specified
problem of m functions in n variables.
This method searches for a zero of a function f(x) between
the given values b and c until the width of the interval
(b,c) has collapsed to within a tolerance specified by
the stopping criterion, Math.abs(b-c) <= 2.0*(rw*Math.abs(b)+ae).
Given an m by n matrix A, an n by n nonsingular diagonal
matrix D, an m-vector b, and a positive number delta,
the problem is to determine a value for the parameter
par such that if x solves the system
The optstp_f77 method determines whether the algorithm should
terminate due to any of the following:
1) problem solved within user tolerance
2) convergence within user tolerance
3) iteration limit reached
4) divergence or too restrictive maximum step (stepmx)
suspected
Translated by Steve Verrill, May 12, 1998.