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.TH mg_weights_build 1 \*(Dt CITRI
.SH NAME
mg_weights_build \- builds the approximate weights file
.SH SYNOPSIS
.B mg_weights_build
[
.B \-h
]
[
.B \-s
]
[
.BI \-b " num"
]
[
.BI \-d " directory"
]
.if n .ti +9n
.BI \-f " name"
.SH DESCRIPTION
.B mg_weights_build
is the program that generates the approximate weights file and the
interleaved text index and exact weights file.  To do this, it uses
the text index and either the exact weights file, or the inverted file
and stemmed dictionary.
.SH OPTIONS
Options may appear in any order.
.TP "\w'\fB\-d\fP \fIdirectory\fP'u+2n"
.B \-h
This displays a usage line on
.IR stderr .
.TP
.B \-s
Save the weights generated from the
.I *.invf
and
.I *.invf.dict
file in a
.I *.weight
file.
.TP
.BI \-b " num"
This specifies the number of bits of precision that should be used for
the approximate weights.  If not specified, it defaults to 8.
.TP
.BI \-d " directory"
This specifies the directory where the document collection is.
.TP
.BI \-f " name"
This specifies the base name of the document collection.
.SH ENVIRONMENT
.TP "\w'\fBMGDATA\fP'u+2n"
.SB MGDATA
If this environment variable exists, then its value is used as the
default directory where the
.BR mg (1)
collection files are.  If this variable does not exist, then the
directory \*(lq\fB.\fP\*(rq is used by default.  The command line
option
.BI \-d " directory"
overrides the directory in
.BR MGDATA .
.SH FILES
.TP 20
.B *.invf
Inverted file.
.TP
.B *.invf.dict
Compressed stemmed dictionary.
.TP
.B *.weight
The exact weights file.
.TP
.B *.text.idx
Index into the compressed documents.
.TP
.B *.text.idx.wgt
Interleaved index into the compressed documents and document weights.
.TP
.B *.weight.approx
Approximate document weights.
.SH "SEE ALSO"
.na
.BR mg (1),
.BR mg_compression_dict (1),
.BR mg_fast_comp_dict (1),
.BR mg_get (1),
.BR mg_invf_dict (1),
.BR mg_invf_dump (1),
.BR mg_invf_rebuild (1),
.BR mg_passes (1),
.BR mg_perf_hash_build (1),
.BR mg_text_estimate (1),
.BR mgbilevel (1),
.BR mgbuild (1),
.BR mgdictlist (1),
.BR mgfelics (1),
.BR mgquery (1),
.BR mgstat (1),
.BR mgtic (1),
.BR mgticbuild (1),
.BR mgticdump (1),
.BR mgticprune (1),
.BR mgticstat (1).