Introduction

The -not option selects records which should be processed. The -not is a not -match. When multiple -match/-not options are used, all must be satisfied.

    wgrib2 -not X (...)

is the same as 

    wgrib2 -match_inv file | egrep -v X | wgrib2 -i (...)



    wgrib2 -match X  -not Y (...)

is the same as 

    wgrib2 -match_inv file | egrep X | egrep -v Y | wgrib2 -i (...)

where X, and Y are regular expressions.  Note, X and Y will not match 
the second (byte location) field of the short inventory.

Usage

-not X

X is a POSIX extended regular expression

The -match, and -not selection facility is more limited than the "wgrib2 | filter | wgrib2 -i" syntax. However, it can be more efficient especially when combined with the -end option.

Future Changes

The format of the "match inventory" has evolved and will continue to evolve. The rule for future changes is that new items in the "match inventory" will be added as the second last item. Consequently the last item in the inventory will always be ":vt=YYYYMMDDHH:". In order to future proof your -match, and -not selections, you must not include any item before the ":vt=YYYYMMDD:" field.

    -match ":vt=2011111500:"                  good
    -not ":vt=2011111500:$"                   good (dollar sign matches the end of the line)
    -not ":n=10:vt=2011111500:"               bad (item before :vt=)
    -match ":RH:975 mb:anl::vt=2010050806:"   bad (item before :vt=)

• adding the "extended name of the variable", ex. TMP.prob_<273
• adding the inventory number, ex. n=10
• adding ensemble/chemical/probability information (-misc)

See also: -not_if, -not_fs, -match, -match_fs, -match_inv, -end, -i, -if, -set_regex.