>> 
<< 
Usr 
Pri 
JfC 
LJ 
Phr 
Dic 
Voc 
!: 
Help 
Dictionary
| Real / Imaginary | +.  0 0 0 | GCD (Or) | 
| +.y yields a two-element list of the real and imaginary parts of 
its argument.  For example, +.3j5 is 3 5, 
and +.3 is 3 0 . 
 |  | x+.y is the greatest common divisor of x 
and y . If the arguments are boolean (0 or 1), 
the functions +. and *. are equivalent to logical or 
and and.  The function -. similarly restricted 
is not. 
 | 
   ]y=: i+2*j. i=: i.4
0 1j2 2j4 3j6
   +. y
0 0
1 2
2 4
3 6
The greatest common divisor divides both of its 
arguments x and y to produce results that have 
no common factor, that is, the GCD of the quotients is 1.  
Moreover, these quotients represent the fraction x%y in lowest form.  
For example:
   x=: 24 [ y=: 60
   x;y;(x +. y);((x , y) % (x +. y))
+--+--+--+---+
|24|60|12|2 5|
+--+--+--+---+
   lff=: , % +.               Gives lowest form of fraction
   x;y;(x lff y);(%/x lff y);(%/x,y);(+./x lff y)
+--+--+---+---+---+-+
|24|60|2 5|0.4|0.4|1|
+--+--+---+---+---+-+
Since the functions =| and =<. 
(tests for non-negative and for integer) produce boolean results, 
the phrase (=|)+.(=<.) is a test for non-negative or 
integer:
   (test=: (=|) +. (=<.)) _2 _2.4 3 3.5
1 0 1 1
The duality of or and and may be shown as follows:
   d (+./ ; *.&.-./ ; *./ ; +.&.-./) d=: 0 1
+---+---+---+---+
|0 1|0 1|0 0|0 0|
|1 1|1 1|0 1|0 1|
+---+---+---+---+
>> 
<< 
Usr 
Pri 
JfC 
LJ 
Phr 
Dic 
Voc 
!: 
Help 
Dictionary