NAG Library Function Document

nag_quad_1d_gauss_wrec (d01tdc)

1

Purpose

2

Specification

3

Description

4

References

5

Arguments

1:    $\mathbf{n}$ – IntegerInput

On entry: $n$, the number of Gauss points required. The resulting quadrature rule will be exact for all polynomials of degree $2n-1$.

Constraint: $\mathbf{n}>0$.

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

On entry: a contains the coefficients $a\left(j\right)$.

3:    $\mathbf{b}\left[\mathbf{n}\right]$ – doubleInput/Output

On entry: b contains the coefficients $b\left(j\right)$.

On exit: elements of b are altered to make the underlying eigenvalue problem symmetric.

4:    $\mathbf{c}\left[\mathbf{n}\right]$ – doubleInput/Output

On entry: c contains the coefficients $c\left(j\right)$.

On exit: elements of c are altered to make the underlying eigenvalue problem symmetric.

5:    $\mathbf{muzero}$ – doubleInput

On entry: muzero contains the definite integral of the weight function for the interval of interest.

6:    $\mathbf{weight}\left[\mathbf{n}\right]$ – doubleOutput

On exit: $\mathbf{weight}\left(j\right)$ contains the weight corresponding to the $j$th abscissa.

7:    $\mathbf{abscis}\left[\mathbf{n}\right]$ – doubleOutput

On exit: $\mathbf{abscis}\left(j\right)$ the $j$th abscissa.

8:    $\mathbf{fail}$ – 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_INT

On entry, $\mathbf{n}=〈\mathit{\text{value}}〉$.
Constraint: $\mathbf{n}\ge 1$.

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.

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Accuracy

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Parallelism and Performance

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Further Comments

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Example

10.1

Program Text

Program Text (d01tdce.c)

10.2

Program Data

10.3

Program Results

Program Results (d01tdce.r)