A method and system for displaying hierarchical data. An orthogonal table structure, which includes a row structure S1, a column structure S2, and an array structure S3, is displayed. S1 and S2 include hierarchical levels of a first hierarchy E1 and a second hierarchy E2, respectively, of linked non-numeric data items. S3 is an array of cells such that every combination of a linear path through S1 and a linear path through S2 has an intersection disposed in the orthogonal table structure at a unique cell of S3. An assignment icon is depicted at each cell of S3, such that selection of the assignment icon at each cell results in displaying data items of a flat vector E3 of non-numeric data items. One of data items of E3 may be selected for insertion or replacement in each cell.