Splitting a numbers binary representation for a double. Post: 302664751

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Homework and Emergencies Homework & Coursework Questions Splitting a numbers binary representation for a double. Post 302664751 by agama on Saturday 30th of June 2012 01:56:49 PM

06-30-2012

Registered User

It would be nice to know what you think isn't working, or where you are stuck. Modulo that, from looking at (not trying to build/execute) your code....

Your approach makes a mountain from a mole hill I think; unless you aren't allowed to use strtoll(). If there are no restrictions, then have a look at the strtoll() manual page, and if you need to add error checking to ensure that a non-hex character hasn't been entered, have a peek at the strspn() manual page too.

If there are restrictions, there still isn't the need for the use of the pow() function; simple (unsigned) character based math and shifting are all that are needed. Consider this example:

Code:

   unsigned char *cval = "123";
    int val = 0;
    int i;

    for( i = 0; i < strlen( cval ); i++ )
    {
        val <<= 4;
        val += cval[i] - '0';
    }
    printf( "%x\n", val );

You'll have to handle a-f and A-F which aren't handled here, but this might point you in the direction of an easier way if strtoll() has to be avoided for the assignment.

Using floating point values for this will make things much more difficult; stick with 64 bit integer. I'd also think about bitwise AND and shift operations as a way to split your key.

agama

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drop_text_search_template

DROP TEXT SEARCH 
TEMPLATE(7)				  PostgreSQL 9.2.7 Documentation			      DROP TEXT SEARCH TEMPLATE(7)

NAME

       DROP_TEXT_SEARCH_TEMPLATE - remove a text search template

SYNOPSIS

       DROP TEXT SEARCH TEMPLATE [ IF EXISTS ] name [ CASCADE | RESTRICT ]

DESCRIPTION

       DROP TEXT SEARCH TEMPLATE drops an existing text search template. You must be a superuser to use this command.

PARAMETERS

       IF EXISTS
	   Do not throw an error if the text search template does not exist. A notice is issued in this case.

       name
	   The name (optionally schema-qualified) of an existing text search template.

       CASCADE
	   Automatically drop objects that depend on the text search template.

       RESTRICT
	   Refuse to drop the text search template if any objects depend on it. This is the default.

EXAMPLES

       Remove the text search template thesaurus:

	   DROP TEXT SEARCH TEMPLATE thesaurus;

       This command will not succeed if there are any existing text search dictionaries that use the template. Add CASCADE to drop such
       dictionaries along with the template.

COMPATIBILITY

       There is no DROP TEXT SEARCH TEMPLATE statement in the SQL standard.

SEE ALSO

       ALTER TEXT SEARCH TEMPLATE (ALTER_TEXT_SEARCH_TEMPLATE(7)), CREATE TEXT SEARCH TEMPLATE (CREATE_TEXT_SEARCH_TEMPLATE(7))

PostgreSQL 9.2.7						    2014-02-17					      DROP TEXT SEARCH TEMPLATE(7)