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JVM structure CONSTANT_Float_info keeps float value
in 4 bytes integer type. I need code to convert float to 4 bytes
according to JVM spec
Thanks a lot

Andy wrote:

>JVM structure CONSTANT_Float_info keeps float value
>in 4 bytes integer type. I need code to convert float to 4 bytes
>according to JVM spec
>Thanks a lot
>
>
float f = ...;
int i = Float.floatToIntBits(f);

See
http://java.sun.com/j2se/1.4.2/docs/...oIntBits(float)

--
Thomas<dot>Fritsch<squiggle>ops<dot>de

On 7 May 2004 07:44:20 -0700, (Andy) wrote or quoted
:

>JVM structure CONSTANT_Float_info keeps float value
>in 4 bytes integer type. I need code to convert float to 4 bytes
>according to JVM spec

That question has nothing to do with softwaretools or the JVM, so I
have snipped those newsgroups.


See Float.intBitsToFloat and Float.floatToIntBits

--
Canadian Mind Products, Roedy Green.
Coaching, problem solving, economical contract programming.
See http://mindprod.com/jgloss/jgloss.html for The Java Glossary.

On Fri, 07 May 2004 18:15:44 GMT, Roedy Green
<roedy-look-on-the-> wrote or quoted :

>
>>JVM structure CONSTANT_Float_info keeps float value
>>in 4 bytes integer type. I need code to convert float to 4 bytes
>>according to JVM spec
>
>That question has nothing to do with softwaretools or the JVM, so I
>have snipped those newsgroups.

see http://mindprod.com/jgloss/newsgroups.html to figure out which one
to pick.

--
Canadian Mind Products, Roedy Green.
Coaching, problem solving, economical contract programming.
See http://mindprod.com/jgloss/jgloss.html for The Java Glossary.

Thanks
But I need piece of code written in C.

>
> >JVM structure CONSTANT_Float_info keeps float value
> >in 4 bytes integer type. I need code to convert float to 4 bytes
> >according to JVM spec
> >Thanks a lot
> >
> >
> float f = ...;
> int i = Float.floatToIntBits(f);
>
> See
>
http://java.sun.com/j2se/1.4.2/docs/...loatToIntBits(
float)
>
> --
> Thomas<dot>Fritsch<squiggle>ops<dot>de
>

Andy wrote:
> Thanks
> But I need piece of code written in C.

Why did you post here then? This is a java group. Anyway (assuming float
and int are both 4 bytes):

unsigned int f_to_ui(float f) { return *((unsigned int *) &f); }
float ui_to_f(unsigned int i) { return *((float *) &i); }

Remember that all of the class file format assumes big endian data,
while your platform might be little endian.

>>>JVM structure CONSTANT_Float_info keeps float value
>>>in 4 bytes integer type. I need code to convert float to 4 bytes
>>>according to JVM spec
>>>Thanks a lot
>>>
>>>
>>
>>float f = ...;
>>int i = Float.floatToIntBits(f);
>>
>>See
>>
>
> http://java.sun.com/j2se/1.4.2/docs/...loatToIntBits(
> float)
>
>>--
>>Thomas<dot>Fritsch<squiggle>ops<dot>de
>>
>
>
>


--
Daniel Sjöblom
Remove _NOSPAM to reply by mail

This is code to convert bytes to float.
I need the reverse of this

bytes
The bytes item of the CONSTANT_Integer_info structure represents
the value of the int constant. The bytes of the value are stored in
big-endian (high byte first) order.

The bytes item of the CONSTANT_Float_info structure represents the
value of the float constant in IEEE 754 floating-point single format
(§3.3.2). The bytes of the single format representation are stored in
big-endian (high byte first) order.

The value represented by the CONSTANT_Float_info structure is
determined as follows. The bytes of the value are first converted into
an int constant bits. Then:

* If bits is 0x7f800000, the float value will be positive
infinity.
* If bits is 0xff800000, the float value will be negative
infinity.
* If bits is in the range 0x7f800001 through 0x7fffffff or in
the range 0xff800001 through 0xffffffff, the float value will be NaN.
* In all other cases, let s, e, and m be three values that
might be computed from bits:

int s = ((bits >> 31) == 0) ? 1 : -1;
int e = ((bits >> 23) & 0xff);
int m = (e == 0) ?
(bits & 0x7fffff) << 1 :
(bits & 0x7fffff) | 0x800000;

Then the float value equals the result of the mathematical expression
s·m·2e-150.

On 10 May 2004 06:26:11 -0700, (Andy) wrote or
quoted :

>This is code to convert bytes to float.
>I need the reverse of this
Please don't cross-post.

See http://mindprod.com/jgloss/converter.html
Version 3.9 now shows you this.

See http://mindprod.com/jgloss/floatingpoint.html
for more detail.
--
Canadian Mind Products, Roedy Green.
Coaching, problem solving, economical contract programming.
See http://mindprod.com/jgloss/jgloss.html for The Java Glossary.