These are programs from the Coyote Library that are specifically identified as being associated with map projections. On-line documentation for these programs is available. A number of program examples using Coyote Map routines can be found in the Coyote Plot Gallery. This utility routine finds the map projection grid boundary from a file, if it is possible to do so. Currently works with GeoTIFF files, CF 1.4 compliant netCDF files, and GPD files created with the GPD_Viewer software from the Catatlyst Library. Note, the authors of the GSHHS software continually change the header structure, which you must know to read the data file. There are are now at least four different structures in common use. Please find the one you need from the commented list in the code itself. The current code uses the structure for the 2.2 version of the GSHHS software. The purpose of this program is to allow the user to browse a very narrow selection of shapefiles. Namely, those containing geographical shapes in latitude and longitude coordinates. In other words, shapefiles containing maps. File attributes are listed in the left-hand list widget. Clicking on a file attribute, will list all the entity attributes for that file attribute in the right-hand list. Clicking an entity attribute with list the type of entity, and the X and Y bounds of that entity (shown as LON and LAT, respectively), in the statusbar at the bottom of the display. Knowing the attribute and entity names of a shapefile will give you insight into how to read and display the information in the file. For examples, see the Coyote Library programs DrawCounties and DrawStates. Source.