I want to implement Sparse Extended information slam. There is four step to implement it. The algorithm is available in Probabilistic Robotics Book at page 310, Table 12.3.
In this algorithm line no:13 is not very clear to me. I have 15 landmarks. So $\mu_t$ will be a vector of (48*1) dimension where (3*1) for pose. Now $H_t^i$ is a matrix whose columns are dynamic as per the algorithm it is (3j-3) and 3j. J is the values of landmarks 1 to 15. Now how could I multiply a dynamic quantity with a static one. There must be a error that matrix dimension mismatch when implement in matlab.
Please help me to understand the algorithm better.