strange calculation results...?

[Jeremy]

hi,

when performing some calculations for display in a table, I
occasionally get the value '04294967295' which is equivalent to 2^32
-1. This value is incorrect as the numbers I'm dealing with are not of
this order.

I know the above details are pretty sketchy, but this looks like some
kind of overflow/underflow. Does anybody have any idea how this number
could crop up?

btw I'm using IBM jdk 1.4.0 on linux.

 

[Jim White]

when performing some calculations for display in a table, I
occasionally get the value '04294967295' which is equivalent to 2^32
-1. This value is incorrect as the numbers I'm dealing with are not of
this order.

I know the above details are pretty sketchy, but this looks like some
kind of overflow/underflow. Does anybody have any idea how this number
could crop up?

Most likely is that you've taken a Java "int" (32 bit two's complement
integer) -1 and converted it to an unsigned integer for display.
Perhaps some code like: ((long) i) & 0xFFFFFFFFL, or something suitable
in your display formatting code to show unsigned.

Jim