When the isotypic subspaces of a representation are viewed as the eigenspaces of a symmetric linear transformation, isotypic projections may be achieved as eigenspace projections and computed using the Lanczos iteration. In this paper, we show how this approach gives rise to an efficient isotypic projection method for permutation representations of distance transitive graphs and the symmetric group.
©2004 Society for Industrial and Applied Mathematics
Maslen, David K., Orrison, Michael E., and Rockmore, Daniel N. "Computing isotypic projections with the Lanczos iteration." SIAM Journal on Matrix Analysis and Applications 25.3 (2004): 784-803.