Level 2 Help for ZIPCOL

INP number 1 is the IBIS interface file being modified.
INP number 2 is the secondary input interface file.

INCOL is used to specify columns in INP number 1, which are used as matching
keys. These keys are in columns X1 to Xk.

OUTCOL is used to specify columns Y1 to Yn of INT1 which will recieve data
when INCOL matches are found.

NULL is used to specify what operation will take place if no match is found
for any keys in INP number 1. If NULL is not specified, the data in columns
Y1 to Yn remain unchanged if a match does not occur. If NULL is specified,
then values C1 to Cn are to be used as data values if no match is found. 

 Same as NULL, used to input a 4 character string.

Columns D1 toDk are the matching keys in the secondary input file. Column
numbers E1 to En specify the columns where data to be transferred to the
OUTCOL columns in INP number 1 are found. The number of 'D' values and 'E'
values must correspond to the number of values following INCOL and OUTCOL
respectively.

Use the keyword 'ALPHA if the matching columns contain alphanumeric 
string data rather than real values.  The files must have been sorted
alphabetically with SORT.