01: // intervallo numeri a virgola mobile, macro sizeof()
02: #include <stdio.h>
03: #include <stdlib.h>
04: #include <float.h> // contiene le costanti usate in questo esempio
05: 
06: int main(int argc, char** argv) {
07: 
08:     printf("Storage size for float : %ld \n", sizeof(float)); // sizeof() restituisce quanti byte occupa un tipo di dato
09:     printf("FLT_MAX     :   %g\n", FLT_MAX);
10:     printf("FLT_MIN     :   %g\n", FLT_MIN);
11:     printf("Number of decimal digits that can be accurately represented: %d\n", FLT_DIG );
12: 
13:     printf("\nStorage size for double : %ld \n", sizeof(double));
14:     printf("DBL_MAX     :   %g\n", DBL_MAX);
15:     printf("DBL_MIN     :   %g\n", DBL_MIN);
16:     printf("Number of decimal digits that can be accurately represented: %d\n", DBL_DIG );
17: 
18:     printf("\nStorage size for long double : %ld \n", sizeof(long double));
19:     printf("LDBL_MAX    :   %Lg\n",  LDBL_MAX);
20:     printf("LDBL_MIN    :   %Lg\n",  LDBL_MIN);
21:     printf("Number of decimal digits that can be accurately represented: %d\n", LDBL_DIG );
22: 
23:     float        fl  = 1.1f; // 23 bit mantissa
24:     double       db  = 1.1;  // 54 bit mantissa
25:     long double  ldb = 1.1L; // 80 bit mantissa
26: 
27:     printf("\nPrecision Examples:\n\n");
28:     printf("float       -> %.30f \t %f\n",  fl, fl);
29:     printf("                 ******\n");
30:     printf("double      -> %.30lf \t %lf\n", db, db);
31:     printf("                 ***************\n");
32:     printf("long double -> %.30Lf \t %Lf\n", ldb, ldb);
33:     printf("                 ******************\n");
34: 
35: 
36:     return 0;
37: }
38: /*
39: Storage size for float : 4 
40: FLT_MAX     :   3.40282e+38
41: FLT_MIN     :   1.17549e-38
42: Number of decimal digits that can be accurately represented: 6
43: 
44: Storage size for double : 8 
45: DBL_MAX     :   1.79769e+308
46: DBL_MIN     :   2.22507e-308
47: Number of decimal digits that can be accurately represented: 15
48: 
49: Storage size for long double : 16 
50: LDBL_MAX    :   1.18973e+4932
51: LDBL_MIN    :   3.3621e-4932
52: Number of decimal digits that can be accurately represented: 18
53: 
54: Precision Examples:
55: 
56: float       -> 1.100000023841857910156250000000    1.100000
57:                  ******
58: double      -> 1.100000000000000088817841970013    1.100000
59:                  ***************
60: long double -> 1.100000000000000000021684043450    1.100000
61:                  ******************
62:   */
63: