expr.py

   1 #!/usr/bin/env python
   2
   3 import math
   4
   5 import torch, torchvision
   6
   7 from torch import nn
   8 from torch.nn import functional as F
   9
  10 def random_var(nb_variables=None, variables=None):
  11     if variables is None:
  12         return chr(ord('A') + torch.randint(nb_variables, (1,)).item())
  13     else:
  14         l = list(variables)
  15         return l[torch.randint(len(l), (1,)).item()]
  16
  17 def random_expr(variables, budget):
  18     if budget <= 5:
  19         op=torch.randint(2, (1,)).item()
  20         if op == 0 and len(variables) > 0:
  21             return random_var(variables=variables)
  22         else:
  23             return str(torch.randint(10, (1,)).item())
  24     else:
  25         op=torch.randint(4, (1,)).item()
  26         if op == 0:
  27             e=random_expr(variables,budget-2)
  28             if ("+" in e or "-" in e or "*" in e) and (e[0]!="(" or e[-1]!=")"):
  29                 return "("+e+")"
  30             else:
  31                 return e
  32         else:
  33             b = 2 + torch.randint(budget-5, (1,)).item()
  34             e1=random_expr(variables,b)
  35             e2=random_expr(variables,budget-b-1)
  36             if op == 1:
  37                 return e1+"+"+e2
  38             elif op == 2:
  39                 return e1+"+"+e2
  40             elif op == 3:
  41                 return e1+"*"+e2
  42
  43 def generate_program(nb_variables, length):
  44     s = ""
  45     variables = set()
  46     while len(s) < length:
  47         v = random_var(nb_variables=nb_variables)
  48         s += v+"="+random_expr(variables,budget = min(20,length-3-len(s)))+";"
  49         variables.add(v)
  50     return s, variables
  51
  52 def generate_sequences(nb, nb_variables = 5, length=20):
  53     sequences=[]
  54     for n in range(nb):
  55         result = None
  56         while result==None or max(result.values())>100:
  57             p,v=generate_program(nb_variables, length)
  58             v=", ".join([ "\""+v+"\": "+v for v in v ])
  59             ldict={}
  60             exec(p+"result={"+v+"}",globals(),ldict)
  61             result=ldict["result"]
  62
  63         k=list(result.keys())
  64         k.sort()
  65         sequences.append(p+" "+";".join([v+":"+str(result[v]) for v in k]))
  66
  67     return sequences
  68
  69 if __name__ == "__main__":
  70     import time
  71     start_time = time.perf_counter()
  72     sequences=generate_sequences(1000)
  73     end_time = time.perf_counter()
  74     for s in sequences[:10]:
  75         print(s)
  76     print(f"{len(sequences) / (end_time - start_time):.02f} samples per second")
  77