chickadee » seulex » seulex-create-solver

(seulex-create-solver XINIT YINIT FCN [JACOBIAN] [AUTONOMOUS] [USER-DATA] [DENSITY-COMPONENTS] [RELTOL] [ABSTOL]) => SEULEX-SOLVERprocedure

Creates and initializes an object representing a problem to be solved with the SEULEX solver.

Arguments XINIT and YINIT represent the initial conditions: XINIT is a scalar value for the independent variable, and YINIT is an SRFI-4 f64vector value containing the initial dependent variable values.

Argument FCN is used to compute the right-hand side function F and must be a procedure of the following form:

(LAMBDA T YY DATA)

or

(LAMBDA T YY)

depending on whether the USER-DATA optional argument is set, where

T
real-valued independent variable
YY
SRFI-4 f64vector with current variable values
DATA
is a user data object (if set)

This procedure must return a SRFI-4 f64vector containing the derivative values.

Optional keyword argument JACOBIAN is a procedure which will be used to compute the partial derivatives of F(X,Y) with respect to Y. If not given, it is computed internally by finite differences.

Optional keyword argument AUTONOMOUS is a boolean value that indicates whether F(X,Y) is independent of X (autonomous) or not (non-autonomous). The default is #t (autonomous).

Optional keyword argument USER-DATA is an object that will be passed as an additional argument to the right-hand side function.

Optional keyword argument DENSITY-COMPONENTS must be an SRFI-4 s32vector which indicates the components for which dense output is required.

Optional keyword arguments RELTOL and ABSTOL specify relative and absolute error tolerance, respectively. These both default to 1e-4.