IBM 5110 User Manual page 32

The catenate function is useful when you are creating lists of
information. Sometimes it is necessary to use an empty array to start
a list. For example, suppose you want to. create a matrix named
PHONE where each row will represent a seven-digit telephone number.
First you want to establish the matrix, then add the telephone numbers
at a later time. The following instruction will establish an empty array
named PHONE with no (0) rows and seven columns:
PHON[~··()
7(.) \ 0
PHONE
Blank display indicates an
.------------------------
pPHDNE
empty array.
o
'7
Now, the telephone numbers can be added as follows:
PHONE~PHONE/[lJ·5336686·
PHONE
~::i:·3366B6
PHONE~PHONE,[lJ'45647'71'
PHONE
~5:·5:·566B6
1+~::j61+
77:1.
(.>PHONE
2
\L.o
7
_ _ _ _ _ _ _ _ _ _ _ The list of telephone numbers
now contains two rows.
APL Language Elements 27