C program

EMPS intranet

Hi! Hi! Start main()

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Value and type of last evaluated expression: Address of array element: Address of array elementx: (none)

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Code

 Header...
 int main(){
   ... 

»  double complex root;
»  double value, err;
»  int expo;

»  printf("Please enter the number whose root is required\n");
»  scanf("%lg", &value);

»  printf("Please enter the integer exponent\n");
»  scanf("%d", &expo);

»  if (expo==0) {
»    printf("The zeroth root is mathematically undefined\n");
»    return 1;
  }

»    root=cpow(value, 1.0/expo);

»  printf("The %dth root of %g is %g %+g i\n", expo, value, 
           creal(root), cimag(root));

  // Test
»  err=cabs(cpow(root, expo)-value);
»  printf("The absolute error is %g\n", err);
»  if (err>1e-12) {
»    printf("ERROR!\n");
»    return 2;
  }

»  return 0;
}

Data

expo (int)			value (double)
132			136
-145183320			4.24399158e-312

err (double)			root (double complex)
144			152
-2.45864802e+267			-9.61809e+266


160
4.94394e-270

Where two numbers are shown the first is the real part, the second the imaginary.

Memory

main()
				132	133	134	135
				expo = -145183320
136	137	138	139	140	141	142	143
value = 4.24399158e-312
144	145	146	147	148	149	150	151
err = -2.45864802e+267
152	153	154	155	156	157	158	159
root_(r) = -9.61809e+266
160	161	162	163	164	165	166	167
root_(i) = 4.94394e-270

NB: the actual memory address of each variable is the
address shown plus 4290974256 (0xFFC31230).

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Output

Please enter the number whose root is required
Please enter the integer exponent
The -145183320th root of 4.24399e-312 is 1 -0 i
The absolute error is 6.87245e-321

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