﻿ frequencies – Algosim documentation
Algosim documentation: frequencies

# frequencies

Computes the count of each distinct element in a container.

## Syntax

• `frequencies(L)`

• `L` is a list or some other suitable container

• `frequencies(L, ε)`

• `L` is a list or some other suitable container

• `ε` is non-negative number

## Description

If `L` is a container, then `frequencies(L)` returns a list of pairs `(x, c)` where each `x` is a distinct element in `L` and the corresponding `c` the number of times that `x` occurs in `L`. Floating-point comparisons are performed without epsilons.

`frequencies(L, ε)` has the same behaviour, except that floating-point comparisons are made with epsilon `ε`.

## Examples

`Alice ≔ ExampleData("Alice in Wonderland") \ 50`
```ALICE’S ADVENTURES IN WONDERLAND

Lewis Carroll
…
```
`SortBy(frequencies(words(Alice)), (x ↦ −x)) \ 20`
```(the, 1515)
(and, 774)
(to, 717)
(a, 610)
(she, 498)
(of, 494)
(it, 482)
(said, 456)
(I, 400)
(Alice, 385)
(in, 353)
(was, 352)
(you, 308)
(that, 257)
(as, 246)
(her, 243)
(at, 199)
(on, 189)
(with, 176)
⋮
```
`sort(frequencies(compute(RandomInt(1000000)^2, n, 1, 1000000) @ digits @ first))`
```(1, 192164)
(2, 146925)
(3, 123873)
(4, 109158)
(5, 98564)
(6, 90439)
(7, 84566)
(8, 79092)
(9, 75219)
```
`frequencies(IdentityMatrix(5))`
```(1, 5)
(0, 20)
```