[FR] Round with decimals

[thareh]

Previous FR here: brl.mod #226

Nice to see a math category!

Perhaps round with decimal precision and a round function that returns a string with the unnecessary bits removed from the end would be a good fit in here somewhere? (math.round or similar?)

I came up with the following solution, but I guess it'd be better to use snprintf directly instead of using TStringBuilder or perhaps there's another even better solution altogether - but here goes:

Private
Global sb:TStringBuilder = New TStringBuilder()

Public

Rem
bbdoc: 
EndRem
Function RoundToString:String(val:Double, decimals:Int)
	sb.SetLength(0)
	sb.FormatDouble("%." + decimals + "f", val)
	Return sb.ToString()
EndFunction

Rem
bbdoc:
EndRem
Function Round:Double(val:Double, decimals:Int)
	Return Double(RoundToString(val, decimals))
EndFunction

Rem
bbdoc:
EndRem
Function RoundToString:String(val:Double, decimals:Int, pretty:Int)
	Local str:String = RoundToString(val, decimals)
	
	If Not pretty
		Return str
	EndIf
	
	For Local i:Int = str.length-1 To 0 Step -1
		If str[i] = 48
			Continue
		EndIf
		
		If str[i] = 46
			Return str[..i]
		EndIf
		
		Return str[..i+1]
	Next
EndFunction

Thanks and a have pleasant day!

[thareh]

Sidenote:
I'm using sb.SetLength(0) to clear the string builder, perhaps a dedicated Clear() method would be a good addition to TStringBuilder as well?

Thanks again!