Using BCD in Module Manager **EXPERIMENTAL** #19
Description
A fellow Kerbonaut approached me in Forum with this suggestion for improvement:
I wrote pretty simple code that shouldn't be too hard to implement in MM to use decimal floats for calculation when it can be represented in decimal and use double for when it can't.
using System;
public class Program
{
static bool DecEval(double num)
{
bool Pass = true;
double UpLimit = 7.9E+28;
double DownLimit = 1E-12;
if (num > UpLimit || num < UpLimit*-1 || (num < DownLimit && num > DownLimit*-1 && num != 0))
{
Pass = false;
}
return Pass;
}
static string Clean0(string str)
{
int WorkingIndex = str.Length-1;
if (str.IndexOf('.') != -1)
{
while (true)
{
if (str[WorkingIndex] == '0')
{
str = str.Substring(0,WorkingIndex);
WorkingIndex = str.Length-1;
} else if(str[WorkingIndex] == '.') {
str = str.Substring(0,WorkingIndex);
break;
} else {break;}
}
}
return str;
}
public static void Main()
{
String NumString1 = "-7.75"; // strings to mimic how ModuleManager starts and saves these numbers
String NumString2 = "7.65";
double Num1 = Convert.ToDouble(NumString1);
double Num2 = Convert.ToDouble(NumString2);
double Num3 = 0;
decimal DecNum1 = 0;
decimal DecNum2 = 0;
decimal DecNum3 = 0;
if (DecEval(Num1) && DecEval(Num2) && DecEval(Num1+Num2))
{
// string scientific notation to decimal doesn't work, so we have to go through a double float.
// The way C# works should prevent any inaccuracies stimming from it, though, as most numbers with 13 digits or less will have a unique value and convert from double properly.
// If they don't, well... it won't be less accurate than only double mathematics.
if (NumString1.ToUpper().IndexOf('E') == -1)
{
DecNum1 = Convert.ToDecimal(NumString1);
} else {
DecNum1 = Convert.ToDecimal(Num1);
}
if (NumString2.ToUpper().IndexOf('E') == -1)
{
DecNum2 = Convert.ToDecimal(NumString2);
} else {
DecNum2 = Convert.ToDecimal(Num2);
}
DecNum3 = DecNum1 + DecNum2;
} else {
Num3 = Num1+Num2;
}
if (Num3 == 0)
{
Console.WriteLine("Returning decimal {0}", Clean0(Convert.ToString(DecNum3)));
} else {
Console.WriteLine("Returning double {0}", Convert.ToString(Num3));
}
}
}
Source: https://dotnetfiddle.net/e2MC24
It sounds logical, but I need to consider that besides being a good idea using Big Numbers instear of floats when possible, this would make MM/L to behave differentlu from Forum's, and I'm unsure if this is a good idea.
The feature is solid, however - it's how MM should be doing things since ever.
Activity
zer0Kerbal commentedon Jan 26, 2023
the forum's MM is dead. Nothing has been done on it that I can see in _how long??? and probably nothing will with the probably pre-release of KSP2 in less than a month.
Lisias commentedon Feb 12, 2023
Fellow Kerbonaut updated his reference code.
Again, this is not exactly the code that will be use, but it demonstrates the feature.