Is it possible to test for NaN?

[AJArmstron@aol.com]

Hello. I want to test a value of a variable for an error message "NaN" (as there has been a division by 0). Can this be done?

Many thanks

[AJArmstron@aol.com]

I have researched this further and recognise that there is a command:
isNan from
Double (Java 2 Platform SE 5.0))

The problem is I do not know how work it with my program. I have a variable called statistics[1] and I want to test to see if it is NaN

I am very thankful for any help.

[masijade]

Double.isNaN(doubleVar)

returns true when it is an NaN. Or

doubleVar != doubleVar

also returns true for an NaN. This, in fact, is the IEEE defined test for NaN and is exactly what isNaN does.

[AJArmstron@aol.com]

I note the program says Double.isNaN(doubleVar)

Does this mean the variable tested has to be a double?

I have an integer called stats2[0]. I want to test it for errors (i.e. isNAN). I have tried using
boolean error=Double.isNaN(stats2[1]);

However, the variable always returns as false (when it is a proper value).

Please help!

[JosAH]

I note the program says Double.isNaN(doubleVar)

Does this mean the variable tested has to be a double?

I have an integer called stats2[0]. I want to test it for errors (i.e. isNAN). I have tried using
boolean error=Double.isNaN(stats2[1]);

However, the variable always returns as false (when it is a proper value).

Please help!

Ints can never be NaN.

kind regards,

Jos

[AJArmstron@aol.com]

JosAH
but somehow mine are!

I worked out what I was doing wrong and have now got the test working successfully.

Thank you.

[masijade]

JosAH
but somehow mine are!

I worked out what I was doing wrong and have now got the test working successfully.

Thank you.

Didn't pay attention to the "fact" that you had an int. In any case, as you've been told ints cannot be NaN. If you claim they are than they are not ints. So, either you have a double, or you have an Integer (not an int) and it is null, and not NaN.

[[RaIdEn]]

the bit of code from your code if displayed would be helpful.

are you trying to divide the result by zero?.