NAG C Library Function Document

nag_reorder_vector (m01esc)

1

Purpose

2

Specification

3

Description

4

References

5

Arguments

1:    $\mathbf{vec}\left[\mathbf{n}\right]$ – Pointer Input/Output

On entry: the array of objects to be rearranged.

On exit: the objects rearranged according to array indices.

2:    $\mathbf{n}$ – size_tInput

On entry: the number, $n$, of objects to be rearranged.

Constraint: $0\le \mathbf{n}\le \mathrm{MAX\_LENGTH}$, where $\mathrm{MAX\_LENGTH}$ is an implementation-dependent value for the maximum size of an array.

3:    $\mathbf{size}$ – size_tInput

On entry: the size of each object to be rearranged.

Constraint: $1\le \mathbf{size}\le p$, where $p$ is an implementation-dependent value for the maximum size_t size on the system, divided by n if n is positive.

4:    $\mathbf{stride}$ – ptrdiff_tInput

On entry: the increment between data items in vec to be rearranged.

Note: if stride is positive, vec should point at the first data object; otherwise vec should point at the last data object.

Constraint: $\mathbf{size}\le \left|\mathbf{stride}\right|\le p$, where $p$ is an implementation-dependent value for the maximum size_t size on the system, divided by n if n is positive.

5:    $\mathbf{indices}\left[\mathbf{n}\right]$ – size_tInput

On entry: the indices specifying the order in which the elements of vector are to be rearranged.

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_2_INT_ARG_LT

On entry, $\left|\mathbf{stride}\right|=〈\mathit{\text{value}}〉$ while $\mathbf{size}=〈\mathit{\text{value}}〉$. These arguments must satisfy $\left|\mathbf{stride}\right|\ge \mathbf{size}$.

NE_ALLOC_FAIL

Dynamic memory allocation failed.

NE_BAD_RANK

Invalid indices vector.

NE_INT_ARG_GT

On entry, $\mathbf{n}=〈\mathit{\text{value}}〉$.
Constraint: $\mathbf{n}\le 〈\mathit{\text{value}}〉$, an implementation-dependent size that is printed in the error message.

On entry, $\mathbf{size}=〈\mathit{\text{value}}〉$.
Constraint: $\mathbf{size}\le 〈\mathit{\text{value}}〉$, an implementation-dependent size that is printed in the error message.

On entry, $\mathbf{stride}=〈\mathit{\text{value}}〉$.
Constraint: $\left|\mathbf{stride}\right|\le 〈\mathit{\text{value}}〉$, an implementation-dependent size that is printed in the error message.

NE_INT_ARG_LT

On entry, $\mathbf{n}=〈\mathit{\text{value}}〉$.
Constraint: $\mathbf{n}\ge 0$.

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

7

Accuracy

8

Parallelism and Performance

9

Further Comments

10

Example

10.1

Program Text

Program Text (m01esce.c)

10.2

Program Data

Program Data (m01esce.d)

10.3

Program Results

Program Results (m01esce.r)