[geran]

If I want to match strings on the following form:

%s %i ( %f %f %f ) (%f %f % f)

where
%s is letters, e.g a string
%i a integer, posetiv or negative
%f a float, can be 0 or 0.0,

ex:

"green" 3 (0 0 0) (-0.4 0.00002 0.222) (4.56 -10.3232 2.533)

or

"red" -6 (0.000012 -0.23131 0.2321) (-0.4 0.00002 0.222) (4.56 -10.3232 2.533)

How can a match these with a regular expression, Im using the regcomp/regexec functions in c.

in Java I would use a expression like this:

\"([a-z]+)\"\\s(-*[0-9]+)\\s\\(\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s\\)\\s\\(\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s\\)

this piece of code should do the trick in Java

Code:

public static void main(String[] args) {
   StringBuffer buf = new StringBuffer("\"origin\"	-1 ( 0 0 0 ) ( -0.4999999404 -0.5000000596 -0.5000000596 )");
   StringBuffer parsed;
   String exp = "\"([a-z]+)\"\\s(-*[0-9]+)\\s\\(\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s\\)\\s\\(\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s(-*[0-9]*\\.*[0-9]*)\\s\\)";
   Pattern p = Pattern.compile(exp);
   Matcher m = p.matcher(buf);
   while(m.find()){
      System.out.println(m.group(0));
      System.out.println(m.group(1));
      System.out.println(m.group(2));
      System.out.println(m.group(3)+","+m.group(4)+","+m.group(5));
      System.out.println(m.group(6)+","+m.group(7)+","+m.group(8));
   }
}

can somebody please help me get this to work in c?

[hayesk]

Search the web for pattern matching code in C. I don't think there is any in the standard C libraries.

[geran]

in the GNU C Library there is pattern matching functions:

regcomp and regexec, look at the man pages, ex man regcomp. I dont get the syntax of the pattern to work as expected.

It's some differences between Java's regular expression and the c implementation, but I can't find any usefull information on how to create the pattern. So what I need is someone that is experinced with the regexec function to help me with the syntax of the pattern.

[geran]

I found the answer, you must set the flag to regcomp to REG_EXTENDED.

then an expresion like:

"\"([a-zA-Z0-9\\_]+)\"[[:space:]]*(-?[0-9]+)[[:space:]]*\\([[:space:]]*(-?[0-9]+[.]*[0-9]*)[[:space:]]*(-?[0-9]+[.]*[0-9]*)[[:space:]]*(-?[0-9]+[.]*[0-9]*)[[:space:]]*\\)[[:space:]]*\\([[:space:]]*(-?[0-9]+[.]*[0-9]*)[[:space:]]*(-?[0-9]+[.]*[0-9]*)[[:space:]]*(-?[0-9]+[.]*[0-9]*)[[:space:]]*\\)

can be used, I just love the documentation ...