Function index

Here is a table of symbols we have used and how to type them in TryAPL.

It might be useful to review this page as you are doing the read and write exercises in the next sections.

New functions

Creating vectors

Symbol	Name	Function (Monadic/Dyadic)	Key combination (Prefix)	Key combination (Tab)
`⍳`	Iota	Index generator	`PREFIX` `I`	`i` `i` `Tab`
`?`	Question mark	Roll / Deal	`PREFIX` `Q`	`?`
`/`	Slash	Replicate	`/`	`/`

Reductions and scans

Symbol	Name	Function (Monadic/Dyadic)	Key combination (Prefix)	Key combination (Tab)
`\`	Backslash	Scan	`\`	`\`

Sorting

Symbol	Name	Function (Monadic/Dyadic)	Key combination (Prefix)	Key combination (Tab)
`⍋`	Grade up	Grade up	`PREFIX` `$`	`A` `\|` `Tab`
`⍒`	Grade down	Grade down	`PREFIX` `#`	`V` `\|` `Tab`

Selecting from a vector

Symbol	Name	Function (Monadic/Dyadic)	Key combination (Prefix)	Key combination (Tab)
`↑`	Up arrow	Take	`PREFIX` `Y`	`^` `\|` `Tab`
`↓`	Down arrow	Drop	`PREFIX` `U`	`v` `\|` `Tab`
`[]`	Brackets	Index	`[` `]`	`[` `]`
`/`	Slash	Compress	`/`	`/`
`⊃`	Right shoe	Pick	`PREFIX` `X`	`)` `)` `Tab`

Searching

Symbol	Name	Function (Monadic/Dyadic)	Key combination (Prefix)	Key combination (Tab)
`⍳`	Iota	Index of	`PREFIX` `I`	`i` `i` `Tab`
`∊`	Epsilon	Member of	`PREFIX` `E`	`e` `e` `Tab`
`⍸`	Iota underbar	Where / Interval index	`PREFIX` `Shift`+`I`	`i` `_` `Tab`
`⍷`	Epsilon underbar	Find	`PREFIX` `Shift`+`E`	`e` `_` `Tab`
`⌸`	Quad equal	Key	`PREFIX` `Shift`+`K`	`[` `=` `Tab`

System variables and constants

Name	Meaning
`⎕A`	The upper-case English alphabet, `'ABCDEFGHIJKLMNOPQRSTUVWXYZ'`
`⎕CT`	Comparison tolerance, from `0` (exact comparison) up to `10*¯10`
`⎕PP`	Print precision, the number of digits displayed
`⎕IO`	Index origin, either `1` (the default) or `0`

Old functions

Symbol	Name	Function (Monadic/Dyadic)	Key combination (Prefix)	Key combination (Tab)
`+`	Plus	Conjugate / Plus	`+`	`+`
`-`	Minus	Negate / Minus	`-`	`-`
`×`	Times	Direction / Times	`PREFIX` `-`	`x` `x` `Tab`
`÷`	Divide	Divide	`PREFIX` `=`	`:` `-` `Tab`
`*`	Star	Power	`*`	`*`
`¯`	High minus	Negative	`PREFIX` `2`	`-` `-` `Tab`
`⍝`	Lamp	Comment	`PREFIX` `,`	`o` `n` `Tab`
`←`	Assignment symbol	Assign	`PREFIX` `[`	`<` `-` `Tab`
`⎕`	Quad	Output	`PREFIX` `L`	`[` `]` `Tab`
`⍴`	Rho	Shape / Reshape	`PREFIX` `R`	`r` `r` `Tab`
`,`	Comma	Ravel / Catenate	`,`	`,`
`{}`	Braces	Dfn	`{` `}`	`{` `}`
`⍺`	Alpha	Left argument	`PREFIX` `A`	`a` `a` `Tab`
`⍵`	Omega	Right argument	`PREFIX` `W`	`w` `w` `Tab`
`⋄`	Diamond	Statement separator	`PREFIX` `	`<` `>` `Tab`
`⍬`	Zilde	Empty numeric vector	`PREFIX` `}`	`0` `~` `Tab`
`⌈`	Upstile	Ceiling / Maximum	`PREFIX` `S`	`7` `7` `Tab`
`⌊`	Downstile	Floor / Minimum	`PREFIX` `D`	`l` `l` `Tab`
`\|`	Stile	Magnitude / Residue	`PREFIX` `M`	`\|`
`∨`	Logical OR	Greatest common divisor, Or	`PREFIX` `9`	`v` `v` `Tab`
`∧`	Logical AND	Lowest common multiple, And	`PREFIX` `0`	`^` `^` `Tab`
`○`	Circle	Pi times / Circular	`PREFIX` `O`	`O` `O` `Tab`
`=`	Equal	Equal to	`PREFIX` `5`	`=`
`≠`	Not equal	Not equal to	`PREFIX` `8`	`=` `/` `Tab`
`<`	Less than	Less than	`PREFIX` `3`	`<`
`≤`	Less than or equal to	Less than or equal to	`PREFIX` `4`	`<` `=` `Tab`
`>`	Greater than	Greater than	`PREFIX` `7`	`>`
`≥`	Greater than or equal to	Greater than or equal to	`PREFIX` `6`	`>` `=` `Tab`
`≡`	Equal underbar	Match	`PREFIX` `:`	`=` `=` `Tab`
`~`	Tilde	Not	`PREFIX` `T`	`~`
`⍲`	Up caret tilde	Nand	`PREFIX` `)`	`^` `~` `Tab`
`⍱`	Down caret tilde	Nor	`PREFIX` `(`	`v` `~` `Tab`
`∇`	Del	Recursion	`PREFIX` `G`	`V` `V` `Tab`
`:`	Colon	Guard	`:`	`:`
`⊣`	Left tack	Same / Left	`PREFIX` `\|`	`-` `\|` `Tab`
`⊢`	Right tack	Same / Right	`PREFIX` `\`	`\|` `-` `Tab`
`⍤`	Jot diaeresis	Atop	`PREFIX` `Shift`+`J`	`o` `:` `Tab`
`∘`	Jot	Bind	`PREFIX` `J`	`o` `o` `Tab`
`/`	Slash	Reduce	`/`	`/`