Harvard:Biophysics 101/2007/Notebook:Resmi Charalel/2007-2-8

Script
#!/usr/bin/env python from random import * mx=10 countH=[0,0,0,0,0,0,0,0,0] countT=[0,0,0,0,0,0,0,0,0] #Generation of list of 10,000 strings of 10 random coinflips and tally of stretches of H's and T's for x in range(10000): s=[] for i in range(mx): random = choice(range(0,2,1)) if random==0: s.append('H') if random==1: s.append('T') substr=''.join(s) for i in range(9): substH = ''.join(['H' for n in range(i+2)]) pos = substr.find(substH,0) while not pos == -1: countH[i] = countH[i] + 1 pos = substr.find(substH,pos+1) for i in range(9): substT = ''.join(['T' for n in range(i+2)]) pos = substr.find(substT,0) while not pos == -1: countT[i] = countT[i] + 1 pos = substr.find(substT,pos+1) print "10,000 strings of 10 random coinflips were generated. The following tallies of H's and T's were recorded." print "Occurence(s) of HH:", countH[0] print "Occurence(s) of HHH:", countH[1] print "Occurence(s) of HHHH:", countH[2] print "Occurence(s) of HHHHH:", countH[3] print "Occurence(s) of HHHHHH:", countH[4] print "Occurence(s) of HHHHHHH:", countH[5] print "Occurence(s) of HHHHHHHH:", countH[6] print "Occurence(s) of HHHHHHHHH:", countH[7] print "Occurence(s) of HHHHHHHHHH:", countH[8] print "Occurence(s) of TT:", countT[0] print "Occurence(s) of TTT:", countT[1] print "Occurence(s) of TTTT:", countT[2] print "Occurence(s) of TTTTT:", countT[3] print "Occurence(s) of TTTTTT:", countT[4] print "Occurence(s) of TTTTTTT:", countT[5] print "Occurence(s) of TTTTTTTT:", countT[6] print "Occurence(s) of TTTTTTTTT:", countT[7] print "Occurence(s) of TTTTTTTTTT:", countT[8]

Output
10,000 strings of 10 random coinflips were generated. The following tallies of H's and T's were recorded. Occurence(s) of HH: 22483 Occurence(s) of HHH: 9995 Occurence(s) of HHHH: 4404 Occurence(s) of HHHHH: 1894 Occurence(s) of HHHHHH: 818 Occurence(s) of HHHHHHH: 342 Occurence(s) of HHHHHHHH: 136 Occurence(s) of HHHHHHHHH: 48 Occurence(s) of HHHHHHHHHH: 14 Occurence(s) of TT: 22591 Occurence(s) of TTT: 10146 Occurence(s) of TTTT: 4492 Occurence(s) of TTTTT: 1905 Occurence(s) of TTTTTT: 771 Occurence(s) of TTTTTTT: 291 Occurence(s) of TTTTTTTT: 108 Occurence(s) of TTTTTTTTT: 36 Occurence(s) of TTTTTTTTTT: 8