Beyond curse of dimensionality

 

In grid method, we basically update the following:

 

In matrix, it is equivalent to

 

Since the maximization is performed column by column, we can calculate

          from j=1 to n

 

Here,  is calculated from  and .

All we have to keep is vector v as well as vector k. We do not have to keep n x n matrix

 

in the calculation.

 

After getting vjf, we apply one of the methods from error bounds to modified policy

 

iterations mentioned before. We can select one of the following:

 

0: no

1:error bounds

2:policy iterations

3:policy iterations with error bounds

4:modified policy iterations

5:modified policy iterations with error bounds

 

We also implement collocation method. The calculation will be done much quicker.