k原题是这样的:
某一游戏中有一把武器有1到9个等级,每次升级成功的概率为30%,失败的概率为70%,成功升1级,失败降1级,降到一级不能再降,升到9级不能再升,问1000次内升到9级的概率是多少?
使用马可夫链的原理,可得到下列矩阵,打一次Pij(第i级到第j级的概率),将这个矩阵自乘1000次,取P19即为所得值
M =
0.7 0.3 0 0 0 0 0 0 0
0.7 0 0.3 0 0 0 0 0 0
0 0.7 0 0.3 0 0 0 0 0
0 0 0.7 0 0.3 0 0 0 0
0 0 0 0.7 0 0.3 0 0 0
0 0 0 0 0.7 0 0.3 0 0
0 0 0 0 0 0.7 0 0.3 0
0 0 0 0 0 0 0.7 0 0.3
0 0 0 0 0 0 0 0 1
算下来是
M^1000 =
0.44293 0.18966 0.08104 0.03446 0.01449 0.00592 0.00225 0.00067 0.22855
0.44254 0.18949 0.08097 0.03443 0.01447 0.00591 0.00224 0.00067 0.22923
0.44125 0.18894 0.08073 0.03433 0.01443 0.00590 0.00224 0.00067 0.23148
0.43784 0.18748 0.08011 0.03407 0.01432 0.00585 0.00222 0.00066 0.23740
0.42952 0.18392 0.07859 0.03342 0.01405 0.00574 0.00218 0.00065 0.25189
0.40973 0.17544 0.07497 0.03188 0.01340 0.00548 0.00208 0.00062 0.28636
0.36320 0.15552 0.06645 0.02826 0.01188 0.00485 0.00184 0.00055 0.36740
0.25431 0.10889 0.04653 0.01978 0.00831 0.00340 0.00129 0.00038 0.55707
0. 0. 0. 0. 0. 0. 0. 0. 1.