SPLINE_CONSTRAINTS

This function returns the derived type array result, ?_SPLINE_CONSTRAINTS, given optional input. There are optional arguments for the derivative index, the value applied to the spline, and the periodic point for any periodic constraint.

The function is used, for entry number j,

 

?_SPLINE_CONSTRAINTS(J) = &

SPLINE_CONSTRAINTS([DERIVATIVE=DERIVATIVE_INDEX,] &

POINT = WHERE_APPLIED, [VALUE=VALUE_APPLIED,], &

TYPE = CONSTRAINT_INDICATOR, &

[PERIODIC_POINT = VALUE_APPLIED])

The square brackets enclose optional arguments. For each constraint either (but not both) the ‘VALUE =’ or the ‘PERIODIC_POINT =’ optional arguments must be present.

Required Arguments

POINT = WHERE_APPLIED (Input)
The point in the data interval where a constraint is to be applied.

TYPE = CONSTRAINT_INDICATOR (Input)
The indicator for the type of constraint the spline function or its derivatives is to satisfy at the point: where_applied. The choices are the character strings ‘==’, ‘<=’, ‘>=’, ‘.=.’, and ‘.=-’. They respectively indicate that the spline value or its derivatives will be equal to, not greater than, not less than, equal to the value of the spline at another point, or equal to the negative of the spline value at another point. These last two constraints are called periodic and negative-periodic, respectively. The alternate independent variable point is value_applied for either periodic constraint. There is a use of periodic constraints in .

Optional Arguments

DERIVATIVE = DERIVATIVE_INDEX (Input)
This is the number of the derivative for the spline to apply the constraint. The value 0 corresponds to the function, the value 1 to the first derivative, etc. If this argument is not present in the list, the value 0 is substituted automatically. Thus a constraint without the derivative listed applies to the spline function.

PERIODIC_POINT = VALUE_APPLIED
This optional argument improves readability by automatically identifying the second independent variable value for periodic constraints.

FORTRAN 90 Interface

Generic: CALL SPLINE_CONSTRAINTS (POINT, TYPE [, …])

Specific: The specific interface names are S_SPLINE_CONSTRAINTS and D_SPLINE_CONSTRAINTS.