C program

EMPS intranet

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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...
#define NX 3
#define NY 2

void normalise (float p[],int n);

 int main(){
   ... 

»  int x, y;
»  float coeffs[NX][NY]={{1,2},{3,4},{5,6}};

  // Normalise the indivdual vectors
»  for (x=0; x<NX; ++x) 
    normalise(coeffs[x], NY);

»  printf("The matrix is:\n");
»  for (x=0; x<NX; ++x) 
    for (y=0; y<NY; ++y) 
      printf("coeffs[%d][%d] is %g\n", x, y, coeffs[x]y);

»  return 0;
}

// Normalise a vector (an array) of length n
 void normalise(float p[],int n){
   ... 

»  float norm=0;
»  int i;

»  for (i=0; i<n; ++i) 
    norm+=pi*pi;
»  norm=sqrt(norm);

»  if (norm>0) {
»    for (i=0; i<n; ++i) 
    pi/=norm;
  }
}

Memory

normalise()
				132	133	134	135
				p = 252
136	137	138	139	140	141	142	143
?	?	?	?	norm = 0
144	145	146	147	148	149	150	151
i = -3767832				?	?	?	?
184	185	186	187	188	189	190	191
?	?	?	?	n = 2

normalise()
				132	133	134	135
				p = 236
136	137	138	139	140	141	142	143
?	?	?	?	norm = 0
144	145	146	147	148	149	150	151
i = -3767832				?	?	?	?
184	185	186	187	188	189	190	191
?	?	?	?	n = 2

normalise()
				132	133	134	135
				p = 244
136	137	138	139	140	141	142	143
?	?	?	?	norm = 0
144	145	146	147	148	149	150	151
i = -3767832				?	?	?	?
184	185	186	187	188	189	190	191
?	?	?	?	n = 2

main()
				228	229	230	231
				x = 1
232	233	234	235	236	237	238	239
y = -3767804				coeffs[0][0] = 1
240	241	242	243	244	245	246	247
coeffs[0][1] = 2				coeffs[1][0] = 3
248	249	250	251	252	253	254	255
coeffs[1][1] = 4				coeffs[2][0] = 5
256	257	258	259
coeffs[2][1] = 6

NB: the actual memory address of each variable is the
address shown plus 4291199176 (0xFFC680C8).

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Output

The matrix is:
coeffs[0][0] is 0.447214
coeffs[0][1] is 0.894427
coeffs[1][0] is 0.6
coeffs[1][1] is 0.8
coeffs[2][0] is 0.640184
coeffs[2][1] is 0.768221

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Code

normalise()

normalise()

normalise()

main()

Output