Format
Format (⍕
) is an ambivalent primitive function which formats the right argument into a simple character array, optionally following the specification supplied as the left argument. The usage of the left argument varies across implementations.
Examples
Monadic form
Format in its monadic form allows the user to convert arrays of any type into simple character arrays (for example for concatenation with other character arrays). The result usually matches the interpreter's default display, either by ⎕←
or by REPL.
supper ← 10 'I ate ',(⍕supper),' shrimp.' I ate 10 shrimp. ⎕←DATA←(⍳3) (2 2⍴⍳4) 'TEXT' 100 1 2 3 1 2 TEXT 100 3 4 ⍕DATA 1 2 3 1 2 TEXT 100 3 4 (⍴DATA) (⍴⍕DATA) 4 2 22
Dyadic form
The dyadic form of Format varies across implementations.
Dyalog APL and NARS2000 support column width and the number of decimal places for formatting numeric arrays. The following example formats the 2-by-3 array with 12 spaces per column, rounded to 2 decimal places:
⎕←C←2 3⍴ 32.10958 0 ¯101.4914 ¯99.40878 ¯101.872 1001.48173 32.10958 0 ¯101.4914 ¯99.40878 ¯101.872 1001.48173 ⍴C 2 3 12 2⍕C 32.11 0.00 ¯101.49 ¯99.41 ¯101.87 1001.48 ⍴(12 2⍕C) 2 36
APLX supports Format by example, which uses string left argument for a rich set of format specifications:
'55.55' ⍕22.234 1.398 11.00 22.23 1.4 11 '55.55 5.555 55.55 55'⍕22.234 1.398 0.00 11.0 22.23 1.398 11 '555,555,555.55'⍕1234567.89 1,234,567.89
See also
External links
Documentation
- Dyalog monadic, dyadic
- NARS2000
- APLX monadic, by specification, by example
- J Dictionary, NuVoc