ERounding.None

[cvdevol]

Now that ERounding.None is gone, how to avoid having the last digit of a EDecimal rounded? I'm investigating repeating decimals in fractions, and it would be nice to have the EDecimal.Divide..... 'ToString' representation end in the exact last digit of the repeating sequence.

[peteroupc]

ERounding.None hasn't been deprecated and is still a supported rounding mode.

[cvdevol]

I get this:(in VB.NET)

Dim EC As EContext = EContext.ForPrecisionAndRounding(100, ERounding.None)

    Dim dv As EDecimal = EDecimal.FromString("1").Divide(EDecimal.FromString("23"), EC)

The result, dv, is an NaN. Shouldn't it be a 100 digit decimal with no rounding?

If I use ERounding.OddOrZeroFiveUp I get:
dv = 0.04347826086956521739130434782608695652173913043478260869565217391304347826086956521739130434782608696

[peteroupc]

It appears that yours is a common issue: EDecimal's Divide method with EContext.None behaves like EDecimal's Divide method with no context; see https://peteroupc.github.io/Numbers/docs/PeterO.Numbers.EDecimal.html. It returns NaN "if the result can't be exact because it would have a nonterminating decimal expansion" (as is the case for 1 divided by 3). See also #3, #8. (I'm just aware of a mixup between "decimal" and "binary" here in the documentation at the moment and will fix it.)

[cvdevol]

IDK. Seems like a bug to me. The other rounding types work fine with non-terminating fractions, and know what to do with the last digit at the specified precision. I've overcome the problem by using a precision that's one greater than the length of the repeating cycle and I simply remove the last (rounded) digit. But it's clunky and requires determining the length of the repeating cycle beforehand.

[mhamri]

this return NaN

var eContext = EContext.ForPrecisionAndRounding(100, ERounding.None);
EDecimal number1Converted = 67;
EDecimal number2Converted = 89;
var result = number1Converted.Divide(number2Converted, eContext);
return result.ToString(); 

and this return 0.7528089887640449438202247191011235955056179775280898876404494382022471910112359550561797752808988764

- var eContext = EContext.ForPrecisionAndRounding(100, ERounding.None);
+ var eContext = EContext.ForPrecisionAndRounding(100, ERounding.down);
EDecimal number1Converted = 67;
EDecimal number2Converted = 89;
var result = number1Converted.Divide(number2Converted, eContext);
return result.ToString(); 

this return NaN

EDecimal number1Converted = 67;
EDecimal number2Converted = 89;
+ var result = number1Converted.DivideToExponent(number2Converted, -100, ERounding.None);
return result.ToString();

look like it's impossible to stop the last digit get rounded