From 6b0284bdece2ea77808548ae52197def2741f874 Mon Sep 17 00:00:00 2001
From: hackbard <hackbard>
Date: Sat, 10 May 2003 16:30:10 +0000
Subject: [PATCH] small improvements
---
ising.c | 163 ++++++++++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 142 insertions(+), 21 deletions(-)
diff --git a/ising.c b/ising.c
index 4ff3ba8..b92cf99 100644
--- a/ising.c
+++ b/ising.c
@@ -7,33 +7,60 @@
*
*/
+#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
#include "dfbapi.h"
#define X 200
#define Y 200
-#define MAX_T 10
+#define I 20
+#define S 1
+
+int usage(void)
+{
+ puts("usage:");
+ puts("");
+ puts("-h \t show this help");
+ puts("-o <file> \t save T - M values to file");
+ puts("-i <value> \t specify itteration value");
+ puts("-x <value> \t # x lattice sites");
+ puts("-y <value> \t # y lattice sites");
+ puts("-s <value> \t spin interaction strength");
+ puts("-r \t run in interactive mode (still in work)");
+
+ return 1;
+}
int main(int argc, char **argv)
{
unsigned char *atom;
- char *arg_v[4];
+ char *arg_v[7];
char m_text[64];
char t_text[64];
char b_text[64];
+ char s_text[64];
+ char output_file[64];
+ int of_fd=0;
int max_x,x_c,max_y,y_c;
int i;
+ int itt;
int count_p;
- unsigned int T;
- double S;
- int M;
+ double T;
+ double s;
+ int M=0;
double beta;
double delta_e;
+ int runfree=0;
+ double max_T;
/* random stuff*/
srand(time(0));
@@ -41,26 +68,111 @@ int main(int argc, char **argv)
/* display stuff */
d2_lattice d2_l;
- /* we will parse argv later ... */
max_x=X;
max_y=Y;
-
+ itt=I;
+ s=S;
+ strcpy(output_file,"");
+ /* parse argv */
+ for(i=1;i<argc;i++)
+ {
+ if(argv[i][0]=='-')
+ {
+ switch(argv[i][1])
+ {
+ case 'x':
+ max_x=atoi(argv[++i]);
+ break;
+ case 'y':
+ max_y=atoi(argv[++i]);
+ break;
+ case 'i':
+ itt=atoi(argv[++i]);
+ break;
+ case 's':
+ s=atof(argv[++i]);
+ break;
+ case 'o':
+ strcpy(output_file,argv[++i]);
+ break;
+ case 'r':
+ runfree=1;
+ break;
+ default:
+ usage();
+ return -1;
+ }
+ } else usage();
+ }
+
+ /* prepare lattice */
d2_lattice_init(&argc,argv,&d2_l,max_x,max_y);
-
atom=(unsigned char *)(malloc(max_x*max_y*sizeof(unsigned char)));
-
d2_l.status=atom;
-
+
+ if(strcmp(output_file,""))
+ {
+ of_fd=open(output_file,O_WRONLY|O_CREAT);
+ if(of_fd<1)
+ {
+ puts("can't open output file ...");
+ return -1;
+ }
+ }
+
/* begin at T=0 M=1 situation */
memset(atom,0,max_x*max_y*sizeof(unsigned char));
+
+ max_T=1.3*s;
+
+ for(T=.05;T<max_T;T+=.05)
+ {
+ beta=1.0/T; /* k_B = 1 */
+ for(i=0;i<itt;i++)
+ {
- S=1; /* i have no idea! */
+ M=0;
+ for(x_c=0;x_c<max_x;x_c++)
+ {
+ for(y_c=0;y_c<max_y;y_c++)
+ {
+ count_p=0;
+ if((*(atom+x_c+((y_c+max_y+1)%max_y)*max_x))&1) ++count_p;
+ if((*(atom+x_c+((y_c+max_y-1)%max_y)*max_x))&1) ++count_p;
+ if((*(atom+((max_x+x_c+1)%max_x)+y_c*max_x))&1) ++count_p;
+ if((*(atom+((max_x+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=(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;
+ }
+ if((*(atom+x_c+y_c*max_x))&1) ++M;
+ }
+ }
- for(T=1;T<MAX_T;T++)
+ sprintf(t_text," temp: %.3f",T);
+ arg_v[1]=t_text;
+ sprintf(b_text," beta: %.3f",beta);
+ arg_v[2]=b_text;
+ arg_v[3]=NULL;
+ sprintf(s_text," interaction strength: %.3f",s);
+ arg_v[4]=s_text;
+ arg_v[5]=NULL;
+ sprintf(m_text," magnetization: %.3f",1.0-2.0*M/(max_x*max_y));
+ arg_v[6]=m_text;
+ d2_lattice_draw(&d2_l,0,0,6,arg_v);
+
+ }
+ if(of_fd) dprintf(of_fd,"%f %f\n",T,1.0-2.0*M/(max_x*max_y));
+ }
+
+ for(T=max_T;T>0;T-=.05)
{
- beta=5.0/T; /* k_B = 1 */
- /* do 100 itterations, we will need more */
- for(i=0;i<100;i++)
+ beta=1.0/T; /* k_B = 1 */
+ for(i=0;i<itt;i++)
{
M=0;
@@ -74,7 +186,7 @@ int main(int argc, char **argv)
if((*(atom+((max_x+x_c+1)%max_x)+y_c*max_x))&1) ++count_p;
if((*(atom+((max_x+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=(2*count_p-4)*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
{
@@ -84,16 +196,25 @@ int main(int argc, char **argv)
if((*(atom+x_c+y_c*max_x))&1) ++M;
}
}
- sprintf(t_text,"temp = %d",T);
+
+ sprintf(t_text," temp = %.3f",T);
arg_v[1]=t_text;
- sprintf(b_text,"beta = %f",beta);
+ sprintf(b_text," beta = %.3f",beta);
arg_v[2]=b_text;
- sprintf(m_text,"magn = %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);
+ arg_v[3]=NULL;
+ sprintf(s_text," interaction strength: %.3f",s);
+ arg_v[4]=s_text;
+ arg_v[5]=NULL;
+ sprintf(m_text," magnetization: %.3f",1.0-2.0*M/(max_x*max_y));
+ arg_v[6]=m_text;
+ d2_lattice_draw(&d2_l,0,0,6,arg_v);
+
}
+ if(of_fd) dprintf(of_fd,"%f %f\n",T,1.0-2.0*M/(max_x*max_y));
}
+ if(of_fd) close(of_fd);
+
getchar();
return 1;
--
2.39.5