Removes selected provenance information from an NDF PROVREM
The ancestors to be removed can be specified either by giving their indices (Parameter ANCESTOR), or by comparing each ancestor with a supplied pattern matching template (Parameter PATTERN).
If an ancestor is hidden rather than deleted (see Parameter HIDE), the ancestor is retained within the NDF, but a flag is set telling later applications to ignore the ancestor (exactly how the flag is used will depend on the particular application).
(!) value is
supplied, the ancestors to be removed are instead determined using the PATTERN
parameter. Each supplied index must be positive and refers to one of the NDFs listed in
the ANCESTORS table in the PROVENANCE extension of the NDF (including any hidden
ancestors). Note, if ancestor indices are determined using the PROVSHOW command, then
PROVSHOW should be run with the HIDE parameter set to FALSE; otherwise incorrect
ancestor indices may be determined, resulting in the wrong ancestors being removed by
PROVREM.
The maximum number of ancestors that can be removed is limited to 100 unless "LL", "*"
or ! is specified. The supplied parameter value can take any of the following
forms.
"ALL" or "*" –- All ancestors.
"xx,yy,zz" –- A list of ancestor indices.
"xx:yy" –- Ancestor indices between xx and yy inclusively. When xx is omitted,
the range begins from 0; when yy is omitted the range ends with the maximum
value it can take, that is the number of ancestors described in the PROVENANCE
extension.
Any reasonable combination of above values separated by commas. [!]
TRUE, then the ancestors are not deleted, but instead have a flag
set indicating that they have been hidden. All information about hidden ancestors is
retained unchanged, and can be viewed using PROVSHOW if the HIDE parameter is set FALSE
when running PROVSHOW. [FALSE] "PATH", "CREATOR" or "DATE". ["PATH"]
TRUE, then the
ancestors specified by Parameter PATTERN or ANCESTORS are removed. Otherwise, these
ancestors are retained and all other ancestors are removed. [TRUE] "_xb" or "_yb". Note, provenance
paths do not include a trailing ".sdf" string. "_ave"
anywhere. "_ave" anywhere. "_d" . The pattern matches "_d" followed by any number of characters
that are not "/", followed by the end of the string. "m51" or "m31". "[chars]" –- Matches any of the characters within the brackets.
"[chars]"
–- Matches any character that is not within the brackets (ignoring the initial
""
character).
"." –- Matches any single character.
"d" –-
Matches a single digit.
"D" –-
Matches anything but a single digit.
"w" –-
Matches any alphanumeric character, and "_".
"W" –-
Matches anything but alphanumeric characters, and "_".
"s" –-
Matches white space.
"S" –-
Matches anything but white space.
Any other character that has no special significance within a regular expression matches itself. Characters that have special significance can be matched by preceding them with a backslash () in which case their special significance is ignored (note, this does not apply to the characters in the set dDsSwW).
Note, minus signs ("-") within brackets have no special significance, so ranges of
characters must be specified explicitly.
The following quantifiers are allowed.
"*" –- Matches zero or more of the preceding atom, choosing the largest possible number
that gives a match.
"*?"–- Matches zero or more of the preceding atom, choosing the smallest possible
number that gives a match.
"+" –- Matches one or more of the preceding atom, choosing the largest possible number
that gives a match.
"+?"–- Matches one or more of the preceding atom, choosing the smallest possible number
that gives a match.
"?" –- Matches zero or one of the preceding atom.
"{n}" –- Matches exactly
occurrences of the preceding atom.
The following constraints are allowed.
"" –-
Matches the start of the test string.
"$" –- Matches the end of the test string.
Multiple templates can be concatenated, using the "|" character to separate them. The
test string is compared against each one in turn until a match is found.