X-Git-Url: https://hackdaworld.org/gitweb/?p=physik%2Fising.git;a=blobdiff_plain;f=ising.c;fp=ising.c;h=e43b4be0a7df9ec7134f9cd5d668f651904e2dc7;hp=dd538b34bd51424fb2a19da036dd0885ef599574;hb=78fcc4451906fd4fbc2830fc72fd511563d9bf98;hpb=0646288c1f9b82c04ff6c74546600e5527c64b2f

diff --git a/ising.c b/ising.c
index dd538b3..e43b4be 100644
--- a/ising.c
+++ b/ising.c
@@ -11,11 +11,12 @@
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>
+#include <time.h>
 #include "dfbapi.h"
 
-#define X 100
-#define Y 100
-#define MAX_T 200
+#define X 200
+#define Y 200
+#define MAX_T 100
 
 int main(int argc, char **argv)
 {
@@ -33,6 +34,9 @@ int main(int argc, char **argv)
  double beta;
  double delta_e;
 
+ /* random stuff*/
+ srand(time(0));
+
  /* display stuff */
  d2_lattice d2_l;
 
@@ -53,9 +57,9 @@ int main(int argc, char **argv)
  
  for(T=1;T<MAX_T;T++)
  {
-  beta=1.0/T; /* k_B = 1 */
-  /* do 100 itterations, we will need more */
-  for(i=0;i<100;i++)
+  beta=20.0/T; /* k_B = 1 */
+  /* do 10 itterations, we will need more */
+  for(i=0;i<10;i++)
   {
 
  for(x_c=0;x_c<max_x;x_c++)
@@ -69,21 +73,21 @@ int main(int argc, char **argv)
    if((*(atom+((2*x_c+1)%max_x)+y_c*max_x))&1) ++count_p;
    if((*(atom+((2*x_c-1)%max_x)+y_c*max_x))&1) ++count_p;
    if(((*(atom+x_c+y_c*max_x))&1)==0) count_p=4-count_p;
-   delta_e=(4-2*count_p)*S;
+   delta_e=(2*count_p-4)*S;
    if(delta_e<0) *(atom+x_c+y_c*max_x)=(*(atom+x_c+y_c*max_x)+1)&1;
    else
    {
     if(1.0*rand()/RAND_MAX<exp(-1.0*delta_e*beta))
      *(atom+x_c+y_c*max_x)=(*(atom+x_c+y_c*max_x)+1)&1;
-    else M+=1;
    }
+   if((*(atom+x_c+((2*y_c+1)%max_y)*max_x))&1) ++M;
   }
  }
   sprintf(t_text,"T = %d",T);
   arg_v[1]=t_text;
   sprintf(b_text,"b = %f",beta);
   arg_v[2]=b_text;
-  sprintf(m_text,"M = %f",1.0-2*M/(max_x*max_y));
+  sprintf(m_text,"M = %f",1.0-2.0*M/(max_x*max_y));
   arg_v[3]=m_text;
   d2_lattice_draw(&d2_l,0,0,3,arg_v);
   }