2 replies to this topic

[PawleysPlayr]

I'm probably doing something utterly stupid. Using the micro framework... The System.Math.ABS will only take a type int...it seems to have only that one overload. Same with System.Math.Round... will take a double, but not a second parameter to specify the number of places to round to. Anyone else seen this?

[Mario Vernari]

The math is something that the MF guys decided to cut enough (IMHO).
Integers are obviously limited for the math, but doubles are too heavy for the MF.
I suggest to use floats unless strictly necessary.

The Abs is straightforward:

public static float Abs(float value)
{
  return (value >= 0) ? value : -value;
}

To round a value by a certain number of decimals, you may use this function:

private static float[] PowersOfTen = new float[]
{
  1.0f,
  10.0f,
  100.0f,
  1000.0f,
  10000.0f,
  100000.0f,
  1000000.0f,
  // etc.
}

public static float Round(float value, int digits)
{
  var power = PowersOfTen[digits];
  return power * (long)(value / power);
}

NOTE: I used an explicit cast to a long, because it does exactly what I need and it is very fast. However a long is much limited in range respect to a float.

Cheers

[PawleysPlayr]

Thanks Mario!