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computer programs
A maximum-entropy formalism aimed at the production of a `maximally noncommittal' map is a standard method in fields of science like radioastronomy, but a rare exception in both X-ray crystallography and electron microscopy (or crystallography). This is rather unfortunate, given the wealth of information that a maximum-entropy map can reveal, especially when the map itself is the end product (for example, low-resolution electron or potential density maps, Patterson functions, deformation maps). The program GraphEnt attempts to automate the procedure of calculating maximum-entropy maps, with emphasis on the calculation of difference Patterson functions for macromolecular crystallographic problems, while providing a useful graphical output of the current stage of the calculation.