Idrisi file names should be given without extensions: gstat assumes the extensions (.dvc, .vec, .doc, .img) to be file-type specific. For instance, when a mask is defined as
mask: 'maskmap';
then gstat assumes the files maskmap.doc and maskmap.img to be present and in the correct idrisi format.
Data can be read from idrisi point files (extensions .dvc and .vec). In the .dvc file, the field id type should be real, file type should be ascii and object type should be point.
Data or grid maps can be read from idrisi image files (extensions .doc and .img). In the .doc file, the field data type should be real, byte or integer, the field file type should be ascii or binary; the fields colums, rows, min X, max Y and resolution should all be set (resolution must be holding the cell size).