BigDecimal to power of BigDecimal

[czarnysfetr]

Hi,

I have a problem with calculating expression, in which I have to use

BigDecimal1 ^ BigDecimal2


BigDecimal.pow() isn't suitable - as far as I know, it requires int as
an parameter, and both my numbers are BigDecimals.


Does anyone know how to handle it?

sfetr

 

[Eric Sosman]

Hi,

I have a problem with calculating expression, in which I have to use

BigDecimal1 ^ BigDecimal2


BigDecimal.pow() isn't suitable - as far as I know, it requires int as
an parameter, and both my numbers are BigDecimals.


Does anyone know how to handle it?

bd1.pow(bd2.intValue()) looks like a good starting point.
If bd2 has a fractional part, you'll need to work harder --
perhaps Math.pow(bd1.doubleValue(), bd2.doubleValue()) would
be of use, followed by conversion from double to BigDecimal.

Seems like a strange thing to want to do, though. I hope
you've got lots of memory ...

 

[Patricia Shanahan]

bd1.pow(bd2.intValue()) looks like a good starting point.
If bd2 has a fractional part, you'll need to work harder --
perhaps Math.pow(bd1.doubleValue(), bd2.doubleValue()) would
be of use, followed by conversion from double to BigDecimal.

Seems like a strange thing to want to do, though. I hope
you've got lots of memory ...

Even if the double approach does not give enough accuracy, it might be a
good starting point for an iterative improvement algorithm such as
Newton-Raphson.

However, it definitely needs to be dome carefully, with attention to
trade-offs between accuracy and memory.

Patricia

 

[czarnysfetr]

Thanks a lot, problem vanished