Add Turbidity Unit

[rgomez90]

Added Turbidity Unit and conversions

• NTU
• mg/l
• ppm

Fixes #825

[rgomez90]

@angularsen I am having issues with the conversions tests.

I suppose I did sth wrong, but I tried to follow the wiki, by giving the conversion values a fixed value.

[lipchev]

Hello,
I'm not at all an expert on the subject- but from what I gather- it is not really possible to relate NTU to concentrations. In fact I'm not really sure what concentration you are referring to here- as the Formazin mixture (I'm told) is made up of two different solutions.
Do you have some other standard in mind?

[codecov-commenter]

Codecov Report

Merging #842 into master will decrease coverage by 0.05%.
The diff coverage is 67.97%.

@@            Coverage Diff             @@
##           master     #842      +/-   ##
==========================================
- Coverage   80.54%   80.49%   -0.06%     
==========================================
  Files         281      283       +2     
  Lines       41925    42276     +351     
==========================================
+ Hits        33770    34031     +261     
- Misses       8155     8245      +90     

Impacted Files	Coverage Δ
UnitsNet/GeneratedCode/UnitAbbreviationsCache.g.cs	100.00% <ø> (ø)
UnitsNet/GeneratedCode/Quantities/Turbidity.g.cs	67.51% <67.51%> (ø)
UnitsNet/GeneratedCode/Quantity.g.cs	81.43% <80.00%> (-0.02%)	⬇️
...ons/GeneratedCode/NumberToTurbidityExtensions.g.cs	100.00% <100.00%> (ø)
UnitsNet/GeneratedCode/UnitConverter.g.cs	100.00% <100.00%> (ø)
...ratedCode/NumberToMassConcentrationExtensions.g.cs	100.00% <0.00%> (ø)
...et/GeneratedCode/Quantities/MassConcentration.g.cs	87.41% <0.00%> (+1.12%)	⬆️

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[rgomez90]

@angularsen @lipchev I think you're right. I am also not a specialist in this type of unity...But yeah, it seems, the conversion depends on a calibration.

So I suppose, we could add NTU without conversions?

[angularsen]

Right, the only way to support these conversions is probably to add something like `myTurbidity.ToMilligramsPerLiter(someReference)` or create a wrapper type `new ReferenceTurbidity(Turbidity.FromNTU(100), someReference).ToMilligramsPerLiter();` but you lose out on much of the generated code benefits. We had similar issues for relative/absolute/gauge pressure conversions. Please see ReferencePressure wrapper type introduced in #726

[rgomez90]

@angularsen I've modified the code and removed the conversions to ppm and mg/l.

I think we could merge it already just adding the new NTU unit.

For the conversion, I think we could go the `myTurbidity.ToMiligramsPerLiter(someReference)' way...

They will be just the 2 conversions, to ppm and to mg/l. So manually adding both methods and tests should not be a headache.

[angularsen]

Ok, merged. Do you plan on adding the conversions later?

[angularsen]

Release UnitsNet/4.71.0 · angularsen/UnitsNet