005-Date of Entry

This field is used to group the newly added records for the convenience of processing. For records added before 14th of May, date of entry is 1995-05-01, and for those added after 14th it is 1995-05-15. This field is inverted as 5 0 "0D-"v5 (It produces a term 0D-1995-05-01; zero is used to make the term appear at the beginning of the dictionary list.)

300-Primary Keywords

This field is used to enter keywords that are not available in the index tool used by the library. In other words, these keywords are local. The field is indexed as:

300 0 (|KW = |v300/) (produces a term KW = Satellite Communication)

301-Controlled Keywords

This field is used to enter keywords assigned using a thesaurus. It is indexed just like the previous keyword field as 301 0 (|KW = |v301/).

To generate the output, search the current date and save the records in a save file. Move to print menu. Select print worksheet, enter the save file name and provide other parameters to print the output in single or multiple column. `Y'to sort the output file. Move to sort worksheet and enter the details as follows:

Exit to generate the list of keywords in the alphabetical order. This output will contain only keywords that are new or wrongly entered. As there is a format exit (mf), it will print all the mfn numbers for a keyword that is new in this set. If the format exit is not used, the data entry operator will have to search the term and find out all the new records that have the new keyword. The mfn command, as in the case of generating compact index as explained in the ISIS manual will print all the mfn numbers including those of terms that are not printed in the list. This will make the list a mess. Therefore, the format exit `mf' can be used to get only the mfns of newly added terms.

How does the Heading Format Work?

If s(mfn) = ref (|("KW = " v1), s(mfn)), then v1/&mf(v1) fi

The first part S(mfn) extracts the mfn number of the first sorted heading as a string. The second part ref (|("KW = "v1), s(mfn)) uses the first heading, i.e. it is a keyword from the new records to locate the term in the inverted file and gets the mfn string of the same. It is assumed that the inverted file is updated after adding the new records. Both these parts together compare the mfn string and if it is same then the term is from the new set (when the ref command is used to extract the mfn, it gets the first mfn only though additional postings exist for the term). If the mfn strings are not the same then the keyword is from any one of the previous set. In the second case the keyword already exists in the database and the format will not print the keyword in the list. The same steps can be used to generate a list of authors or other fields wherever consistency check is required. Remember to change the sort FST to change the field tag and format.

Programme Listing

program mf (s1 : string;|w, occ: real; s2: string) [FORMAT];
    var urs, sep : string;
    un, f, urn : real;
{Program to put mfn numbers for a selected heading from the INV file}
begin
    f: = find (`KW = `|s1);
    if f = 0 then begin un : = nxtpost;
repeat
    urn : = posting (`MFN');
urs : = encint (urn, 0);
    if size (s2)>0 then sep: = `,' else sep: = ";
    s2 : = s2|sep|urs;
    un : = nxtpost;
"until un <0; end, urs: = ", urn = 0, sep. = ", end.

Sample Output

Full listing of dictionary terms of keywords in a database with 4 records :

    KW = ADHESIVES
    KW = CHEMICAL REACTIONS
    KW = COMMUNICATION SATELLITES
    KW = SPACE COMMERCIALISATION

Though the last two records contain all the above index terms the output generated is as follow:

    Adhesives
    3, 4
    Chemical Reactions
    3

- N. Narayanan Kutty & K. Mohana Kumar
VSSC Library, ISRO Post, Kerala, India - 695 022
Email : root%vssct@sirnetm.ernet.in