Consider the following computational problem (or rather, task):
- An array of $A$ of (not necessarily distinct) elements from a fully-ordered finite domain
- An ordered sequence pivot values $p_1 \ldots p_m$ (i.e. such that $i < j \implies p_i < p_j$).
A partition of $A$ into $m+1$ parts (be they sets or shorter arrays), denoted $A'_0 \ldots A'_m$ , such that if $i < j$ and $x \in A'_i$ then $x < p_j$.
One could call this computing a "histogram with variable-size bins", or "m-pivoting", or "m-way ordered partitioning", etc.
But are there names for this task which are more commonly used than others?
PS - If it helps, we can relax the requirement on the pivots to $p_i \leq p_j$.