feat(useMath): new function

[FrankFang]

Description

import { useMath } from '@vueuse/math'

const value = ref(45.95)
const rounded = useMath('round', value)
// rounded.value is 46
const floored = useMath('floor', value)
// floored.value is 45

Additional context

#1812

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[zojize]

ideally, I'd love to use this function like this:

const {
  ceiled, // 43
  floored, // 42
  // better names?
  absed, // 42.42
  sqrted, // 6.513063795173513
  sign, // 1
} = useMath(42.42)

[antfu]

For reference: https://github.com/vueuse/vue-chemistry#usage

[FrankFang]

#1844 is better. close pr.

[FrankFang]

@zojize It looks good, But it's a little strange that the props of result depends on the number of params:

const {floored} = useMath(1.1) // no powed
const {powed} = useMath(2, 2) // no floored

[zojize]

@zojize It looks good, But it's a little strange that the props of result depends on the number of params:

const {floored} = useMath(1.1) // no powed
const {powed} = useMath(2, 2) // no floored

IMO in case of multiple arguments, it should be returned as a function.

e.g.

const { pow } = useMath(3)
const squared = pow(2) // ref(9)
const cubed = pow(3) // ref(27)