NAG CL Interface
e01bhc (dim1_​monotonic_​intg)

1 Purpose

2 Specification

3 Description

4 References

5 Arguments

1: $\mathbf{n}$ – Integer Input

On entry: n must be unchanged from the previous call of e01bec.

2: $\mathbf{x}\left[\mathbf{n}\right]$ – const double Input

3: $\mathbf{f}\left[\mathbf{n}\right]$ – const double Input

4: $\mathbf{d}\left[\mathbf{n}\right]$ – const double Input

On entry: x, f and d must be unchanged from the previous call of e01bec.

5: $\mathbf{a}$ – double Input

6: $\mathbf{b}$ – double Input

On entry: the interval $[a,b]$ over which integration is to be performed.

7: $\mathbf{integral}$ – double * Output

On exit: the value of the definite integral of the interpolant over the interval $[a,b]$.

8: $\mathbf{fail}$ – NagError * Input/Output

The NAG error argument (see Section 7 in the Introduction to the NAG Library CL Interface).

6 Error Indicators and Warnings

NE_INT_ARG_LT

On entry, $\mathbf{n}=⟨\mathit{\text{value}}⟩$.
Constraint: $\mathbf{n}\ge 2$.

NE_NOT_MONOTONIC

On entry, $\mathbf{x}\left[r-1\right]\ge \mathbf{x}\left[r\right]$ for $r=⟨\mathit{\text{value}}⟩$ : $\mathbf{x}\left[r-1\right]=⟨\mathit{\text{value}}⟩$, $\mathbf{x}\left[r\right]=⟨\mathit{\text{value}}⟩$.
The values of $\mathbf{x}\left[\mathit{r}\right]$, for $\mathit{r}=0,1,\dots ,n-1$, are not in strictly increasing order.

NW_INTERVAL_EXTRAPOLATE

On entry, limits a, b must not be outside interval $[\mathbf{x}\left[0\right],\mathbf{x}\left[n-1\right]]$, $\mathbf{a}=⟨\mathit{\text{value}}⟩$, $\mathbf{b}=⟨\mathit{\text{value}}⟩$, $\mathbf{x}\left[0\right]=⟨\mathit{\text{value}}⟩$, $\mathbf{x}\left[⟨\mathit{\text{value}}⟩\right]=⟨\mathit{\text{value}}⟩$. Extrapolation was performed to compute the integral. The value returned is, therefore, unreliable.

7 Accuracy

8 Parallelism and Performance

9 Further Comments

10 Example

10.1 Program Text

10.2 Program Data

10.3 Program Results