NAG Library Function Document

nag_1d_ratnl_eval (e01rbc)

1

Purpose

2

Specification

3

Description

4

References

5

Arguments

1:    $\mathbf{m}$ – IntegerInput

On entry: $m$, the number of terms in the continued fraction.

Constraint: $\mathbf{m}\ge 1$.

2:    $\mathbf{a}\left[\mathbf{m}\right]$ – const doubleInput

On entry: $\mathbf{a}\left[\mathit{j}-1\right]$ must be set to the value of the parameter $a_{\mathit{j}}$ in the continued fraction, for $\mathit{j}=1,2,\dots ,m$.

3:    $\mathbf{u}\left[\mathbf{m}\right]$ – const doubleInput

On entry: $\mathbf{u}\left[\mathit{j}-1\right]$ must be set to the value of the parameter $u_{\mathit{j}}$ in the continued fraction, for $\mathit{j}=1,2,\dots ,m-1$. (The element $\mathbf{u}\left[m-1\right]$ is not used).

4:    $\mathbf{x}$ – doubleInput

On entry: the value of $x$ at which the continued fraction is to be evaluated.

5:    $\mathbf{f}$ – double *Output

On exit: the value of the continued fraction corresponding to the value of $x$.

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

The NAG error argument (see Section 3.7 in How to Use the NAG Library and its Documentation).

6

Error Indicators and Warnings

NE_ALLOC_FAIL

Dynamic memory allocation failed.
See Section 2.3.1.2 in How to Use the NAG Library and its Documentation for further information.

NE_BAD_PARAM

On entry, argument $〈\mathit{\text{value}}〉$ had an illegal value.

NE_INTERNAL_ERROR

An internal error has occurred in this function. Check the function call and any array sizes. If the call is correct then please contact NAG for assistance.
See Section 2.7.6 in How to Use the NAG Library and its Documentation for further information.

NE_NO_LICENCE

Your licence key may have expired or may not have been installed correctly.
See Section 2.7.5 in How to Use the NAG Library and its Documentation for further information.

NE_POLE_PRESENT

x corresponds to a pole of $R\left(x\right)$, or is very close. $\mathbf{x}=〈\mathit{\text{value}}〉$.

7

Accuracy

8

Parallelism and Performance

9

Further Comments

10

Example

10.1

Program Text

Program Text (e01rbce.c)

10.2

Program Data

Program Data (e01rbce.d)

10.3

Program Results

Program Results (e01rbce.r)