Here is a list of all documented modules with brief descriptions:

Mbicubic_interp_mod	Bicubic interpolation routines for scalars and vectors
Mbilinear_interp_mod	Bilinear interpolation routines for scalars and vectors
Mbudget_interp_mod	Budget interpolation routines for scalars and vectors
Mearth_radius_mod	Determine earth radius and shape
Mgdswzd_c_mod	Module that contains C wrapper for routine gdswzd()
Mgdswzd_mod	Driver module for gdswzd routines
Mip_constants_mod	Module containing common constants
Mip_equid_cylind_grid_mod	Equidistant cylindrical grib decoder and grid coordinate transformations
Mip_gaussian_grid_mod	Gaussian grid coordinate transformations
Mip_grid_descriptor_mod	Users derived type grid descriptor objects to abstract away the raw GRIB1 and GRIB2 grid definitions
Mip_grid_factory_mod	Routines for creating an ip_grid given a Grib descriptor
Mip_grid_mod	Abstract ip_grid type
Mip_grids_mod	Re-export the individual grids
Mip_interpolators_mod	Top-level module to export interpolation routines and constants
Mip_lambert_conf_grid_mod	Lambert conformal grib decoder and grid coordinate transformations
Mip_mercator_grid_mod	GDS wizard for mercator cylindrical
Mip_mod	Top-level module for the ip library which re-exports public routines such as ipolates, ipolatev, and gdswzd
Mip_polar_stereo_grid_mod	GDS wizard for polar stereographic azimuthal
Mip_rot_equid_cylind_egrid_mod	Rotated equidistant cylindrical GRIB decoder and grid coordinate transformations for Arakawa grid E
Mip_rot_equid_cylind_grid_mod	Rotated equidistant cylindrical GRIB decoder and grid coordinate transformations for Arakawa grids A through D
Mip_station_points_grid_mod	Interpolate gridded data to a series of station points
Mipolates_mod	Top-level driver for scalar interpolation interpolation routine ipolates()
Mipolatev_mod	Top-level driver for vector interpolation interpolation routine ipolatev()
Mneighbor_budget_interp_mod	Interpolate scalar fields (neighbor)
Mneighbor_interp_mod	Interpolate scalar fields (neighbor)
Mpolfix_mod	Make multiple pole scalar values consistent
Mspectral_interp_mod	Interpolate spectral