SUBROUTINE WGHTLS(N,ARG)

Performs various operations to do with weights for LSQ, either for
PR or simpler applications. applications.

Arguments:

On entry N=1 means find an L WGHT card and read from it the type of

weighting to be used, with default = 1. ARG is irrelevant.

N=2 means from ARG, IWGHT etc make a weight to go with this OBS
N=3 means given WT, get WDIFF and SQRTWT. ARG is included for

diagnostic purposes only, and is sometimes used as the argument, or sometimes the observation.

Calls:

ERRIN2 JFIX MESS ONCARD

Common blocks used:

/IOUNIT/ to use LPT

/OBSCAL/ to use OBS DIFF IWGH WT SQRTWT WDIFF

/SOURCE/ to use JSOURC KSOURC

*** WGHTLS updated by JCM 23 Mar 92 ***

SUBROUTINE WGHTSF

Deals with weights of LSQ observations for single crystal.

Description:

Puts weight of current observation into WT, its square root into SQRTWT, and WDIFF = SQRTWT times difference, all according to IWGHT.

Calls:

TESTOV

Called by:

CHILSQ MAGLSQ MMPLSQ MPLSQ PALSQ SFLSQ SFTLSQ

Common blocks used:

/OBSCAL/ to use DIFF WT SQRTWT WDIFF

*** WGHTSF argument H removed by PJB 12-July 1999 ***

FUNCTION WIYPOS(Y)

Returns \$\exp(y^2){\textrm errf}(y)\$ for positive \$y\$
only

*** WIYPOS by WIFD 6-JUNE-84 ***

SUBROUTINE WTMEAN(X,DX,IFUN,SUMS)

Multiple entry routine for the calculation of weighted averages.

Arguments:

On entry IFUN indicates which action is required:

IFUN= 0 initialses an array SUMS for subsequent summing.
IFUN= a positive integer adds an observation X with a weight

deduced from the value of IFUN:
IFUN=1 gives unit weights
IFUN=2 gives 1/DX squared

IFUN= a negative integer returns the mean in X, the standard

deviation in DX, and the number of observations in the 4th element of given array SUMS.

If an observation has zero DX, it is ignored. -ve DX is treated as +ve.
SUMS is a 1x5 array holding values for an individual set of data, so that

several sets may be collected simultaneously.

SUMS HOLDS:

Sum of weighted observations
Sum of weighted squares of observations
Sum of 1/DX squared
Number of observations
Denominator for mean

If unit weights, this is the number of observations,
If 1/DX sqrd weights this is the sum of the weights

Calls:

GMZER

Called by:

ABSCOR STATIS ARRINC ARRNGE PATHS INCMSF MEANWT SORGAM

*** WTMEAN corrected by PJB 21-Oct-97 ***