The Schindler Transform (ST) [1] can speed up the block sorting phase of the Burrows- Wheeler Transform (BWT) by limiting the context sorting to the first k (k ?? [0,N], where N is the length of the text) positions only. Under the ST?fs partial sorting scheme, if two rows share the exactly same k-order context, they may not be ordered alphabetically; instead, the relative order between them in the original matrix is preserved in the transformed matrix.