Is there a floatN_t type ? Post: 302323082

Sponsored Content

Top Forums Programming Is there a floatN_t type ? Post 302323082 by emitrax on Friday 5th of June 2009 10:34:49 AM

06-05-2009

Registered User

Quote:

Originally Posted by mgessner

There are 3 floating point types in C, as of C99:

float
double
long double

There are minimum sizes for these. The size for float on many machines is 32 bits, and for double 64 bits. On one of my machines, sizeof (long double) == 16 (128 bits).

I don't think glibc defines any new ones.

I can't rely on the common size used. They must be 8,16, etc.. bits

Quote:

Originally Posted by mgessner

None of this is stopping you from doing your own floating point type representations using 8 or 16 bits, but you'll have to do it in the integer space and convert it. This isn't really that hard.

If you're passing these around on a network, you need to be very careful about the binary representations of these things, because there may be different floating point representations than what you're expecting.

HTH

I think I'm going with my own representation, although a ready-to-use would
have been appreciated. Do you have any link/suggestion?

Up to 64 bits, I could typedef uintN_t to floatN_t for containing the variable.
While for float128_t I was thinking of

Code:

typedef struct {
   float64_t low;
   float64_t high;
} float128_t;

but as for interpreting and producing a value I'm not sure about how to do it.

And no, I'm not passing them around networks.

Thanks,
S.

emitrax

View Public Profile for emitrax

Find all posts by emitrax

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

you have more and one unix type?

As a formem unix newbe I Just wanted to tell you about this cool site for all you confused people. If you need to support more than one unix type: Use this one. It's a life saver. http://www.unixguide.net/unixguide.shtml here

2. Shell Programming and Scripting

Different type of shells?

Hello there, i just want to know what are the different type of shells and the main difference betwee them. The problem is that if you try to search over the net you will find a lot of information and hence you will have no enough time to read all of them.....Anyone can help with this??

3. Shell Programming and Scripting

String type to date type

Can one string type variable changed into the date type variable.

4. Programming

array type has incomplete element type

Dear colleagues, One of my friend have a problem with c code. While compiling a c program it displays a message like "array type has incomplete element type". Any body can provide a solution for it. Jaganadh.G

5. Solaris

raid type

how to get the raid type of a mount if I am using solaris disksuite? thanks

6. UNIX for Dummies Questions & Answers

Encoding Type

Hi, Where can I find the encoding type in a unix server ? Thanks in advance !!!

7. UNIX for Dummies Questions & Answers

key_t type

I would like to print value of key generate like this.... key_t k = ftok(".",'c'); printf("key is %d \n" , k); Is there other way to print this type. I dont think I am getting right output which is key is 1662074913 (shouldn't it be 6362074913) since 'c' is 63 in hex (ascii table)....

8. Windows & DOS: Issues & Discussions

Type of RAM

Hello All Is there a way I can find out the type of RAM (DDR1 or DDR2 or DDR3), I'm using withoout opening the cabinet? Any Windows command? Thanks in advance.

9. Programming

Changing type name

In C++, how can I change the type with another name For example How can I declaring an object real which would be the same as declaring it float

LEARN ABOUT BSD

platform

platform(n)						       Tcl Bundled Packages						       platform(n)

__________________________________________________________________________________________________________________________________________________

NAME

       platform - System identification support code and utilities

SYNOPSIS

       package require platform ?1.0.4?

       platform::generic
       platform::identify
       platform::patterns identifier
_________________________________________________________________

DESCRIPTION

       The platform package provides several utility commands useful for the identification of the architecture of a machine running Tcl.

       Whilst Tcl provides the tcl_platform array for identifying the current architecture (in particular, the platform and machine elements) this
       is not always sufficient. This is because (on Unix machines) tcl_platform reflects the values returned by the uname command and	these  are
       not standardized across platforms and architectures. In addition, on at least one platform (AIX) the tcl_platform(machine) contains the CPU
       serial number.

       Consequently, individual applications need to manipulate the values in tcl_platform (along with the output of system specific utilities)  -
       which is both inconvenient for developers, and introduces the potential for inconsistencies in identifying architectures and in naming con-
       ventions.

       The platform package prevents such fragmentation - i.e., it establishes a standard naming convention  for  architectures  running  Tcl  and
       makes it more convenient for developers to identify the current architecture a Tcl program is running on.

COMMANDS

       platform::identify
	      This  command returns an identifier describing the platform the Tcl core is running on. The returned identifier has the general for-
	      mat OS-CPU. The OS part of the identifier may contain details like kernel version, libc version, etc., and this information may con-
	      tain dashes as well.  The CPU part will not contain dashes, making the preceding dash the last dash in the result.

       platform::generic
	      This  command  returns a simplified identifier describing the platform the Tcl core is running on. In contrast to platform::identify
	      it leaves out details like kernel version, libc version, etc. The returned identifier has the general format OS-CPU.

       platform::patterns  identifier
	      This command takes an identifier as returned by platform::identify and returns a list of identifiers describing compatible architec-
	      tures.

KEYWORDS

       operating system, cpu architecture, platform, architecture

platform							       1.0.4							       platform(n)