# System Function UCS

## Universal Character Set - ⎕UCS (System Function) - available in monadic form only,but with TWO different types of argument calls:

 Z←⎕UCS R Universal Character Set.     R should be a character string OR set of integers to enumerate.
R is  1) a character scalar or character String OR   2) scalar integer or set of Integers     to enumerate.
Z is a scalar or vector of results(integer or string, inverse of call.

Examples, working with ⎕UCS:

```        ⎕UCS 'ABC'        ⍝Type 1(CHAR string) - Locate index positions for letters A, B and C in the Universal Character Set.
65 66 67                  ⍝Letters A, B and C FOUND at index positions 65, 66 and 67 in ⎕UCS.
⍴⎕UCS 'ABC'       ⍝Determine the shape of the result of the call to UCS.
3

⎕AV⍳'ABC'         ⍝Comparable call to ⎕AV using Iota, but the same letters('ABC').
66 67 68                  ⍝>> 66 67 68 << using ⎕AV versus >> 65 66 67 << using ⎕UCS - similar, but NOT identical results.

⎕UCS 65 66 67 68 69   ⍝Type 2(INTEGERS vector) - Find characters associated with integer positions in Universal Character Set.
ABCDE                     ⍝Letters A, B, C, D and E 'ABCDE' returned, as a string.
⍴⎕UCS 65 66 67 68 69  ⍝Determine the shape of the result.
5

⎕UCS "012345⍴⍳6789"   ⍝Another character string - with digits, rho(⍴) and iota(⍳) - also enumerated.
48 49 50 51 52 53 9076 9075 54 55 56 57      ⍝Note how Rho and Iota are much higher in the UCS than letters and digit-characters.
```

System Variables (A value may be assigned to these except for ⎕DM)
ALX CT DM DT ELX FC FEATURE FPC IC IO
LR LX PP PR PW RL SA WSID
Niladic System Functions (a value cannot be assigned to these)
A AV EM ET LC NNAMES NNUMS SI SYSID SYSVER
T TC TCBEL TCBS TCESC TCFF TCHT TCLF TCNL TCNUL
TS WA
Monadic or dyadic system functions (a value cannot be assigned to these)
AT CR DC DL DR EA EC ERROR ES EX
FMT FX MF NAPPEND NC NCREATE NERASE NINFO NL NLOCK
NREAD NRENAME NREPLACE NRESIZE NSIZE NTIE NUNTIE STOP TF TRACE
UCS VR
Note that quad functions and variables (except for the ⎕A family of functions) are case insensitive