NAG C Library Function Document

nag_summary_stats_onevar_combine (g01auc)

1

Purpose

2

Specification

3

Description

4

References

5

Arguments

1:    $\mathbf{b}$ – IntegerInput

On entry: $b$, the number of blocks the full dataset was split into.

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

2:    $\mathbf{mrcomm}\left[20\times \mathbf{b}\right]$ – const doubleCommunication Array

Note: where $\mathbf{MRCOMM}\left(i,j\right)$ appears in this document, it refers to the array element $\mathbf{mrcomm}\left[\left(j-1\right)\times 20+i-1\right]$.

On entry: the $j$th column of mrcomm must contain the information returned in rcomm from one of the runs of nag_summary_stats_onevar (g01atc).

3:    $\mathbf{pn}$ – Integer *Output

On exit: the number of valid observations, that is the number of observations with $w_i>0$, for $\mathit{i}=1,2,\dots ,n$.

4:    $\mathbf{xmean}$ – double *Output

On exit: $\stackrel{-}{x}$, the mean.

5:    $\mathbf{xsd}$ – double *Output

On exit: $s_2$, the standard deviation.

6:    $\mathbf{xskew}$ – double *Output

On exit: $s_3$, the coefficient of skewness.

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

On exit: $s_4$, the coefficient of kurtosis.

8:    $\mathbf{xmin}$ – double *Output

On exit: the smallest value.

9:    $\mathbf{xmax}$ – double *Output

On exit: the largest value.

10:  $\mathbf{rcomm}\left[\mathit{dim}\right]$ – doubleCommunication Array

Note: the dimension, dim, of the array rcomm must be at least

• $20$, when $\mathbf{rcomm}\text{is not}\mathbf{NULL}$.

On exit: an amalgamation of the information held in mrcomm. This is in the same format as rcomm from nag_summary_stats_onevar (g01atc).

If rcomm is NULL, rcomm is not referenced.

11:  $\mathbf{fail}$ – 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_CASES_ONE

On exit we were unable to calculate xsd, xskew or xkurt. A value of $0$ has been returned.

NE_CASES_ZERO

On entry, the number of valid observations is zero.

NE_ILLEGAL_COMM

On entry, mrcomm is not in the expected format.

NE_INT

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

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.

NE_ZERO_VARIANCE

On exit we were unable to calculate xskew or xkurt. A value of $0$ has been returned.

7

Accuracy

8

Parallelism and Performance

9

Further Comments

10

Example

10.1

Program Text

Program Text (g01auce.c)

10.2

Program Data

Program Data (g01auce.d)

10.3

Program Results

Program Results (g01auce.r)