Alignments are also useful for multi-language text editors. We have extended the Emacs text editor to maintain correspondences and identify anomalies between translations. Scrolling or highlighting in one document will scroll or highlight the corresponding region of the other document. Selecting positions on the residual plot that have a large slope will often identify discrepancies in the translations.

In some cases it is useful to automatically reorder sequences. Re-translation is a service offered by AT&T Business Translation to simplify translating a new version of a previously translated document. Only the differences between the versions need to be translated. The file names and boundaries are typically different in the new version, however, so the file pairs must be determined before the differences can be identified. Diagonals can be reconstructed by an image processing algorithm that identifies the clearest diagonal on a strip of grid boxes. Automatic diagonal reconstruction identifies file pairs in reordered versions, which is a crucial first step in comparing versions of large systems or documents that have diverged over time.