random 'doubles'

[Jeremy Watts]

how would you produce a random decimal number in java, say 0.05663?

i can seem to produce random integers but not doubles


thanks

 

[Daniel Dyer]

how would you produce a random decimal number in java, say 0.05663?
http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Math.html#random()

or

http://java.sun.com/j2se/1.5.0/docs/api/java/util/Random.html#nextDouble()

i can seem to produce random integers but not doubles

How?

Dan.

 

[Oliver Wong]

How?

To the OP, if you're in some special environment where you can generate
random integers but not doubles (J2ME perhaps?), you can just divide your
integers to turn them into decimal values.

<pseudoCode>
Generate a random integer between zero and a million.
Divide that integer by a million to get a decimal value between 0 and 1.
</pseudoCode>

However, if you have access to the nextDouble() method mentioned above,
you should probably use it, as it may produce "better" (more random?)
results.

- Oliver

 

[Tony Morris]

To the OP, if you're in some special environment where you can
generate

random integers but not doubles (J2ME perhaps?), you can just divide your
integers to turn them into decimal values.

// not using constant expressions (JLS 15.28)
x = 7;
y = 4;
System.out.println(x/y); // prints 1, not 1.75

 

[Roedy Green]

how would you produce a random decimal number in java, say 0.05663?

i can seem to produce random integers but not doubles

see http://mindprod.com/jgloss/randomnumbers.html

 

[Luc The Perverse]

// not using constant expressions (JLS 15.28)
x = 7;
y = 4;
System.out.println(x/y); // prints 1, not 1.75

Of course - this is integer division.

You need to cast to some type of floating point.

 

[Stefan Ram]

Of course - this is integer division.

This depends on the context these four lines are embedded in:

public class Main
{ public static void main( final java.lang.String[] args )
{ double x; double y;
// not using constant expressions (JLS 15.28)
x = 7;
y = 4;
System.out.println(x/y); // prints 1, not 1.75
}}

 

[Tony Morris]

Of course - this is integer division.

This depends on the context these four lines are embedded in:

public class Main
{ public static void main( final java.lang.String[] args )
{ double x; double y;
// not using constant expressions (JLS 15.28)
x = 7;
y = 4;
System.out.println(x/y); // prints 1, not 1.75
}}

I'm sure I typed int before those declarations.
I'm going to email my nntp provider for filtering out my int declarations!

 

[Luc The Perverse]

Of course - this is integer division.

This depends on the context these four lines are embedded in:

public class Main
{ public static void main( final java.lang.String[] args )
{ double x; double y;
// not using constant expressions (JLS 15.28)
x = 7;
y = 4;
System.out.println(x/y); // prints 1, not 1.75
}}

Not if it's printing out 1 instead of 1.75

 

[Noodles Jefferson]

how would you produce a random decimal number in java, say 0.05663?

i can seem to produce random integers but not doubles

Math.random() will.

StrictMath.random() will too.


--
Noodles Jefferson
mhm31x9 Smeeter#29 WSD#30
sTaRShInE_mOOnBeAm aT HoTmAil dOt CoM

NP: "Icicle" (Tour Rehearsal) -- Tori Amos

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are common, children no longer obey their parents and the end of the
world is evidently approaching."
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