BigDecimal Exception

[inspired]

Based on advice provided on an earlier post, I am trying to use the
BigDecimal class. However, I`m having a fundamental problem.

In my application class, I have the following:

private static final BigDecimal LSBvalue = (new BigDecimal (180 *
( Math.pow(2, 1 - 15)))).setScale(5, RoundingMode.HALF_UP);

public static int convertToInt(BigDecimal degrees) throws
ArithmeticException
{
return (degrees.divide(LSBvalue)).intValue();
}


The simple call below:

BigDecimal AngleDegrees = new BigDecimal(0.9118);
int AngleBams = convertToInt(AngleDegrees);

results in the following exception:

java.lang.ArithmeticException: Non-terminating decimal expansion; no
exact representable decimal result.
at java.math.BigDecimal.divide(BigDecimal.java:1603)
at BamBam.Angle.convertToInt(Angle.java:47)
at BamBam.Angle.main(Angle.java:73)


I am new to BigDecimal and not sure what I am doing wrong. Can
anyone help?

Alan

 

[Arne Vajhøj]

Based on advice provided on an earlier post, I am trying to use the
BigDecimal class. However, I`m having a fundamental problem.

In my application class, I have the following:

private static final BigDecimal LSBvalue = (new BigDecimal (180 *
( Math.pow(2, 1 - 15)))).setScale(5, RoundingMode.HALF_UP);

public static int convertToInt(BigDecimal degrees) throws
ArithmeticException
{
return (degrees.divide(LSBvalue)).intValue();
}


The simple call below:

BigDecimal AngleDegrees = new BigDecimal(0.9118);
int AngleBams = convertToInt(AngleDegrees);

results in the following exception:

java.lang.ArithmeticException: Non-terminating decimal expansion; no
exact representable decimal result.
at java.math.BigDecimal.divide(BigDecimal.java:1603)
at BamBam.Angle.convertToInt(Angle.java:47)
at BamBam.Angle.main(Angle.java:73)


I am new to BigDecimal and not sure what I am doing wrong. Can
anyone help?

BigDecimal is exact.

And it seems as you are making a calculation that requires an
infinite number of decimals to represent the result.

Maybe you really want floating point and just have to live
with its behavior.

Arne

 

[ClassCastException]

BigDecimal is exact.

And it seems as you are making a calculation that requires an infinite
number of decimals to represent the result.

Maybe you really want floating point and just have to live with its
behavior.

BigDecimal can be used at finite precision, or you can set a precision in
a MathContext object and pass it to all your BigDecimal arithmetic
operations.

(Or you can use a JVM language like Clojure that has a ratio type, which
is exact and can represent any rational fraction. )