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A conjunction together with one of its arguments produces an adverb defined in an obvious way. For example, if a1=: &3 ,then ^ a1 is equivalent to ^&3 3 (the cube function), and if a2=: 3& then ^ a2 is equivalent to 3&^ (the three-to-the-power function). It is therefore easy to define useful families of adverbs from a conjunction, so easy that it is fruitless to attempt an exhaustive catalogue. The following list is intended to suggest the possibilities in various classes:

 a0=: I=: ^:_1 Inverse (^I is ^.) a1=: L=: ^:_ Limit (2&o.L 1 for soln of y=cos y) a2=: LI=: ^:__ Limit of inverse a3=: SQ=: ^:2 Square (1&o.SQ for sine squared) a4=: C=: &o. Family of circular fns (3 C is tangent) a5=: CO=: %@C 3 CO is cotangent m6=: rfd=: 1r180p1&* Radians from degrees m7=: dfr=: rfd I Use dfr=: dfr f. to fix definition a8=: D=: @rfd Try 1 C D 0 30 45 60 90 180 m9=: SIN=: 1&o. D Sine for degree arguments a10=: T=: "2 Try

Explicit Definitions

An adverb or a conjunction can be defined in explicit form. For example:

```   split=: 2 : ',.@(x.@(y.&{.) ; x.@(y.&}.))'
]x=: i. 5 3
0  1  2
3  4  5
6  7  8
9 10 11
12 13 14

(+: split 2 ,. |. split 3 ,. +/ split 2) x
+--------+--------+--------+
|0 2  4  |6 7 8   |3 5 7   |
|6 8 10  |3 4 5   |        |
|        |0 1 2   |        |
+--------+--------+--------+
|12 14 16|12 13 14|27 30 33|
|18 20 22| 9 10 11|        |
|24 26 28|        |        |
+--------+--------+--------+
```
 c15=: split=: 2 : ',.@(x.@(y.&{.) ; x.@(y.&}.))' split as defined above d16=: by=: ' '&;@,.@[,.] Verb for use in the table adverb below d17=: over=: ({.;}.)@":@, Verb for use in the table adverb below a18=: table=: 1 :'[ by ]over x./' Try 1 2 3 * table 4 5 6 7

Noun Arguments

Adverbs that apply to a noun argument, and conjunctions that apply to one noun argument and one verb argument are commonplace. For example:

```   x=: 0 0 1 1 [ y=: 0 1 0 1
x *. y			NB. Boolean and
0 0 0 1

x 1 b. y			NB. Boolean adverb
0 0 0 1

x (i.16) b. y		NB. All sixteen Boolean functions
0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1
0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1
0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1
0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1

C=: 1 : 'x.&o.'              NB. Circle adverb
1 C 0 1r4p1 1r3p1 1r2p1 1p1	NB. Sine function
0 0.7071068 0.8660254 1 0

^&3 x=: i. 6	 		NB. Cube
0 1 8 27 64 125

2 |. !. 1 x			NB. Shift in ones
2 3 4 5 1 1
```

Conjunctions that apply to two nouns are less familiar, although the definitions of functions in terms of nouns occur frequently in math. For example, a rational function (the quotient of a polynomial a&p. divided by another b&p.) is defined by a pair of coefficients. Thus:

```   a=: 1 4 6 4 1 [ b=: 1 2 1
RAT=: 2 : 'x.&p. % y.&p.'
a RAT b
1 4 6 4 1&p. % 1 2 1&p.

a RAT b y=: i.6
1 4 9 16 25 36

b RAT a y
1 0.25 0.111111 0.0625 0.04 0.0277778

(a RAT b * b RAT a) y
1 1 1 1 1 1
```

We may also remark that expressions such as 2 x3 and 2 x3 + 4 x2 are commonly used in elementary math to define functions rather than to indicate explicit computation: the x in the foregoing can be construed (and defined) as a conjunction such that 2 x 3 is the function 2:*]^3: . Thus:

```   x=: 2 : 'x.&* @ (^&y.) " 0'
2 x 3
2&*@(^&3)"0

2 x 3 y=: 0 1 2 3 4 5
0 2 16 54 128 250

2 * y ^ 3
0 2 16 54 128 250

2 3 5 x 1 2 4 y
0  0    0
2  3    5
4 12   80
6 27  405
8 48 1280
10 75 3125
```

The last result above gave the values of the individual terms; in order to obtain their sums (and yet retain the behaviour for a single term), we redefine the conjunction x as follows:

```   x=: 2 : '+/ @ (x.&* @ (^&y.)) " 0'
2 3 5 x 1 2 4 y
0 10 96 438 1336 3210

(2 x 1 + 3 x 2 + 5 x 4) y
0 10 96 438 1336 3210

2 x 3 y
0 2 16 54 128 250
```
 c19=: RAT=: 2 : 'x.&p. % y.&p.' Produces rational function c20=: x=: 2 : '+/ @ (x.&* @ (^&y.)) " 0' Mimics notation of elementary math c21=: bind=: 2 : 'x. @ (y."_)' Binds y to the monad x

It is often convenient to bind an argument to a monad, producing a function that ignores its argument. For example, using wdinfo , a monad that displays its argument in a message box, the definition fini=: wdinfo bind 'Job Finished' produces a function such that fini'' is equivalent to wdinfo 'Job Finished' .

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