./guide
unflag.pro

Last modification date:

Wed Sep 28 13:27:09 2016

unflag

procedure unflag, id, [/keep], [/all]

Remove all flags with the same idstring value, or id number, from the flag file associated with the current input spectral line data file or output (keep) data file.

The flag is completely removed from the flag file using this command. Use flag or flagrec to re-flag the data.

If ID is an integer, then that is the first value given in the listflag output. Note that this ID reflects the state of the flags at that particular moment. A particular rule's ID number will change if a rule appearing earlier in the flags (having a lower ID number) is unflagged. ID numbers always run from 0 to one less than the total number of flag rules. IDs given in a single call to unflag (i.e. as a vector of IDs) are valid for that use of unflag - renumbering effectively does not happen until unflag returns. Note that this behavior of ID has a practical consequence that may not be obvious, see the examples.

Continuum flagging is not supported.

If /all is set then all flags are unflagged and ID is ignored if set.

Examples

You use list flags and see that there are 5 flags, numbered from 0 to 4. For this example, assume that you did not specify an idstring when the current 1, 2, and 4 rules were made using flag and so the idstring for those 3 rules is "unspecified".

Unflag all of these rules in one use of unflag.

    unflag,'unspecified'
 

Flags are now numbered just 0 and 1.

Alternatively, starting from the same place as the previous example, suppose you just want to unflag one of those "unspecified" ID rules. This example does that for ID number 2.

    unflag, 2
 

Flags are now numbered 0 through 3 and the "unspecified" rules are now 1 and 3.

Finally, again starting from the same starting place, suppose you want to unflag IDs 2 and 4 but leave ID from the set of "unspecified" rules. There are two ways you can do this.

    unflag, [2,4]
 

That is the easiest way. Flags are now numbered from 0 to 2 and ID 1 is still "unspecified". This is the other way to achieve the same result.

    unflag, 4
    unflag, 2
 

Note here that doing it one ID at a time, you must make sure that you remove the IDs in reverse order or re-check the IDs using listflags prior to each use of unflag. That is because the IDs are renumbered as a consequence of each use of unflag. This generates an error:

    unflag, 2
    unflag, 4
 

because after the first call, IDs run from 0 to 3 and ID 4 no longer exists. If there were more than 5 IDs to start with, this last call would not generate any error and would also not be what you thought you were doing. Always make sure that you use listflag before each use of unflag and when you want to unflag several IDs, use the array syntax and remove them all with a single use of unflag to avoid confusion.

Version

$Id$

Parameters
id in, required string,long	The idstring to match, or a unique id integer. If this parameter is of type string, all flags that match this string will be removed from the flag file. If it is an integer type, only that particular id will be removed. An array of IDs can be used here. All of those IDs will be unflagged.

Keywords
keep in, optional boolean	Unflag the keep (output) data source.
all in, optional boolean	Unflag all IDs (ignoring id) when set.