https://github.com/mjendrusch/metric

Dimensionful types for Nim.
https://github.com/mjendrusch/metric

dimensional-analysis nim si-units units-of-measure units-of-measurement

Last synced: 3 months ago
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Dimensionful types for Nim.

• Host: GitHub
• URL: https://github.com/mjendrusch/metric
• Owner: mjendrusch
• License: mit
• Created: 2018-02-25T21:46:41.000Z (over 6 years ago)
• Default Branch: master
• Last Pushed: 2018-08-07T13:21:57.000Z (over 6 years ago)
• Last Synced: 2024-05-18T14:33:57.269Z (6 months ago)
• Topics: dimensional-analysis, nim, si-units, units-of-measure, units-of-measurement
• Language: Nim
• Size: 9.77 KB
• Stars: 18
• Watchers: 2
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-nim - metric - A small library providing type-level dimensional analysis. (Science / Embedded)

README

        
# metric - bringing SI to Nim

[![nimble](https://raw.githubusercontent.com/yglukhov/nimble-tag/master/nimble_js.png)](https://github.com/yglukhov/nimble-tag)

`metric` is a small library providing type-level dimensional analysis.

It allows you to keep track of the physical units of your programs, and can

be useful for writing scientific software.

## Installation

`metric` has no non-standard dependencies. Just type `nimble install metric`

and you're good to go.

## A small usage example

```nim

import metric, strformat

## Let's open a block with a lot of miscellaneous units predefinded:

withUnits:

  var

    v0 = 40.0 * mile / hour # Some non-SI units of velocity.

  echo "v0 in miles per hour: ", fmt"{v0 as mile / hour} [mph]"

  echo "v0 in decimeters per fortnight: ",

    fmt"{v0 as dm / (2.0 * week)} [dm / fortnight]"

  echo "v0 in SI units: ", v0

```

As you can see, `metric` makes it easy to handle units, and never have to

worry about keeping track of strange conversions.

## Custom dimensions

`metric` provides the means to handle all dimensionful quantities under the

SI system. Dimensions taken into consideration are:

* `Length`

* `Time`

* `Mass`

* `Amount`

* `Temperature`

* `Current`

* `Intensity`

Should you need different units, you can do that, by just defining them as

`object of BaseDimension`, with the following procs and constants:

```nim

type

  MyDimension = object of BaseDimension

proc `$`(x: typedesc[MyDimension]): string = "mydim" ## \

  ## Define how you want your dimension's base unit to be pretty-printed.

const

  myUnitValue = Unit[MyDimension](val: 1.0) ## The name does not matter here.

```

With those things defined, you are good to use your units in the same way, as

the built-ins.