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Examples

Random examples

Mean of a list
```
   F:{/+%N
   F1 2 3 4
2.5
   F1 2 3 4 5
3.0
```
Explanation: {/+%N) defines a fork. The superfluous ending brace can be dropped. Let's denote the argument as Y. When we call the function, it gets interpreted as (/+Y)%(NY).
- /+ gives the sum of a list
- % divides the left argument by the right argument
- N gives the length of a list
Factorial
```
   Fac:/*-,1R
   MFacR10
[1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880]
```
Explanation: Fac is a chain. When you call FacY, it gets evaluated as /*-,1RY.
- /* gives the product of the given list
- -, removes the items of the left argument from the right argument. Because no left argument was given, it removes zeroes.
- 1R gives a list from 1 to the argument, inclusive
- R10 gives a list from 0 to 9
- MFac maps Fac to them
Fibonacci sequence
```
   F:2Lr0 1/v;$l/+@2ER
   F10
[0, 1, 1, 2, 3, 5, 8, 13, 21, 34]
```
Explanation: Here we see a lot of new features. Let's look at what each function does from right-to-left * R gives a range from 0 to x. * ;$l/+@2E takes a list as it's right argument and appends the sum of the two last elements to it. * 2E takes the last two elements * /+ sums them * ; concats two values * x F$lG y gets evaluated as y F x G y * 0 1/v right-folds the list, starting with the value of [0, 1]. This is the magic. * 2Lr drops the last two elements. Without it, two extra numbers would be returned.

Count letters in a word

   F:VO$rME{M;C)$r-u
   F"this is a sentence"
e 3
  3
s 3
n 2
i 2
t 2
c 1
a 1
h 1

Explanation coming soon.

Code golf examples

Home on the Range of Lists
```
   F:/+lM]R
   F10
[0, [1, [2, [3, [4, [5, [6, [7, [8, [9]]]]]]]]]]
   F3
[0, [1, [2]]]
   F2
[0, [1]]
   F1
[0]
   F0
[]
```
Explanation: Function definition initiates a chain of functions. The function is evaluated as /+,(M](RY)) or X/+,(XM](XRY)), depending on if it's called monadically or dyadically.
- R gives the range from 0 to Y.
- M] wraps every element to a list.
- /+l gives the fold of +l, which returns x + [y]