C program

EMPS intranet

Hi! Hi! Start main()

Try stepping through the code

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

Your browser does not support the canvas element which will make some the features unavailable.

If you are using Internet Explorer within the University of Exeter try going to the Settings menu (probably the gear shape at the top right of this page), selecting "Compatibility View settings", unchecking "Display intranet sites in Compatibility View" and reloading this page.

Code

 Header...
//
// Multiply two matrices together: A = B x C
//
 void matmul(int nx,int ny,int nz,float a[][ny],
      float b[][nz],float c[][ny]){
   ... 

»  int x, y, z;

»  for (x=0; x<nx; ++x) {
»    for (y=0; y<ny; ++y) {
»      a[x]y=0.0;
»      for (z=0; z<nz; ++z) 
  a[x]y+=b[x]z*c[z]y;
}
  }
}
#define NX 2
#define NY 3
#define NZ 2
 int main(){
   ... 

»  float a[NX][NY], b[NX][NZ]={{1,2},{3,4}}, 
    c[NZ][NY]={{1,-1,-2},{2,-2,-3}};
  
»  matmul(NX, NY, NZ, a, b, c);
»  return 0;
}

Memory

matmul()
				132	133	134	135
				c = 308
136	137	138	139	140	141	142	143
b = 268				a = 284
144	145	146	147	148	149	150	151
?	?	?	?	x = 134538298
152	153	154	155	156	157	158	159
y = -144480933				z = 2055650816
208	209	210	211	212	213	214	215
nx = 2				ny = 3
216	217	218	219
nz = 2

main()
				268	269	270	271
				b[0][0] = 1
272	273	274	275	276	277	278	279
b[0][1] = 2				b[1][0] = 3
280	281	282	283	284	285	286	287
b[1][1] = 4				a[0][0] = -4.60314e+33
288	289	290	291	292	293	294	295
a[0][1] = 2.01101e-33				a[0][2] = 3.99931e-34
296	297	298	299	300	301	302	303
a[1][0] = 3.99922e-34				a[1][1] = 1.4013e-45
304	305	306	307	308	309	310	311
a[1][2] = -nan				c[0][0] = 1
312	313	314	315	316	317	318	319
c[0][1] = -1				c[0][2] = -2
320	321	322	323	324	325	326	327
c[1][0] = 2				c[1][1] = -2
328	329	330	331
c[1][2] = -3

NB: the actual memory address of each variable is the
address shown plus 4292275120 (0xFFD6EBB0).

Show Advanced options

Validate Link-check

Try stepping through the code

Code

matmul()

main()