Added big random instances

instances/big-random/generator.py

@@ -0,0 +1,43 @@
+import sys
+import random
+print ("Script name: %s" % str(sys.argv[0]))
+print ("node number: %s" % str(sys.argv[1]))
+print ("density: %s" % str(sys.argv[2]))
+print ("random seed: %s" % str(sys.argv[3]))
+n=int(sys.argv[1])
+p=n/2
+dens=float(sys.argv[2])
+ssd=int(sys.argv[3])
+
+random.seed(ssd)
+e=0
+edge=[[],[]]
+for i in range (n):
+    for j in range (i+1,n):
+        if random.random()<dens:
+            edge[0].append(i)
+            edge[1].append(j)
+            e=e+1
+
+
+outname = 'graph_'+str(n)+'_'+str(dens)+'_'+str(ssd)+'.txt'
+f = open (outname,'w')
+f.write('%d\n' % n)
+f.write('%d\n' % e)
+if (2*p == n):
+    f.write('%d\n' % p)
+else:
+    f.write('%d\n' % (p+1))
+for i in range (e):
+    f.write('%d %d \n' % (edge[0][i],edge[1][i]))
+for i in range (0,2*p,2):
+    f.write('%d %d \n' % (i, i+1))
+if (2*p < n):
+    f.write('%d \n' % (n))
+f.close()
+
+print("expected edges %d --- actual edges %d \n" % (dens*n*(n-1)/2, e))
+
+f = open ("graph_list.txt",'a+')
+f.write('%s \n' % outname)
+f.close()