public subroutine dintdy(T, K, Yh, Nyh, Dky, Iflag)
DESCRIPTION
DINTDY computes interpolated values of the K-th derivative of the
dependent variable vector y, and stores it in DKY. This routine
is called within the package with K = 0 and T = TOUT, but may
also be called by the user for any K up to the current order.
(See detailed instructions in the usage documentation.)
The computed values in DKY are gotten by interpolation using the
Nordsieck history array YH. This array corresponds uniquely to a
vector-valued polynomial of degree NQCUR or less, and DKY is set
to the K-th derivative of this polynomial at T.
The formula for DKY is:
where c(j,K) = j(j-1)…*(j-K+1), q = NQCUR, tn = TCUR, h = HCUR.
The quantities nq = NQCUR, l = nq+1, N = NEQ, tn, and h are
communicated by COMMON. The above sum is done in reverse order.
IFLAG is returned negative if either K or T is out of bounds.
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Nodes of different colours represent the following:
Solid arrows point from a procedure to one which it calls. Dashed
arrows point from an interface to procedures which implement that interface.
This could include the module procedures in a generic interface or the
implementation in a submodule of an interface in a parent module.