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Floating divide by zero

The program in Listing 4 attempts to divide the double value of -11 by the double value of zero.

No runtime error with floating divide by zero

In the case of floating types, an attempt to divide by zero does not produce a runtime error. Rather, it returns a value that the println method interprets and displays as either Infinity or -Infinity .

What is the actual value?

The actual value returned by the division operation in this program is the value of a static final variable in the Double class named NEGATIVE_INFINITY . (There is also a value for POSITIVE_INFINITY .)

Is this a better approach?

As you learned earlier, if you attempt to divide by zero with integer arithmetic, an exception will be thrown. Is this a better approach than throwing an exception?I will let you be the judge of that. The important thing is that you know what will happen in both cases and beprepared to deal with the consequences.

In either case, you could test the right operand before the divide to ensure that it isn't equal to zero, and then take appropriate action if it is zero.

Cannot use exception handling in this case

For floating divide by zero, you cannot handle the problem by using try-catch because an error or exception won't be thrown.However, you can test the result following the divide to see if it is equal to either of the infinity values mentioned above . Note, however, that you will need to test against the constant values shown above and not against the output produced by the println method.

And the correct answer to the question is...

C. -Infinity

Mixed-type arithmetic

What output is produced by the program shown in Listing 5 ?

  • A. Compiler Error
  • B. Runtime Error
  • C. 4.294967294E9
  • D. 4294967294
Listing 5 . Mixed-type arithmetic.
public class Mixed01{ public static void main(String args[]){ new Worker().doWork();}//end main() }//end class definitionclass Worker{ public void doWork(){//Integer.MAX_VALUE = 2147483647 int myIntVar = Integer.MAX_VALUE;System.out.println(2.0 * myIntVar); }//end doWork()}//end class definition

This program illustrates the use of arithmetic operators with operands of different types.

Declare and initialize an int

The method named doWork declares a local variable of type int named myIntVar and initializes it with the largest positive value that can be stored in type int .

Evaluate an arithmetic expression

An arithmetic expression involving myIntVar is evaluated and the result is passed as a parameter to the println method where it is displayed on the computer screen.

Multiply by a literal double value

The arithmetic expression uses the multiplication operator (*) to multiply the integer value stored in myIntVar by 2.0 (this literal operand is type double by default) .

Automatic conversion to wider type

When arithmetic is performed using operands of different types, the type of the operand of the narrower type is automatically converted to the type of the operand of the wider type, and the arithmetic is performed on the basis of the wider type.

(By narrower and wider, we mean the width of the range of values that can be accommodated by the type in question.)

Questions & Answers

what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
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Source:  OpenStax, Ap computer science a, clarification of the java subset. OpenStax CNX. Oct 03, 2015 Download for free at https://legacy.cnx.org/content/col11279/1.5
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