Latitude/Longitude Triangular Grid on a Sphere

**SPHERE_LLT_GRID**,
a MATLAB library which
uses longitudes and latitudes to create grids of points, lines,
and triangles
over the surface of a sphere in 3D.

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

**SPHERE_LLT_GRID** is available in
a C version and
a C++ version and
a FORTRAN90 version and
a MATLAB version and
a Python version.

BALL_GRID, a MATLAB library which computes a grid of points over the interior of a ball in 3D.

CIRCLE_ARC_GRID, a MATLAB program which computes points equally spaced along a circular arc;

CUBE_GRID, a MATLAB library which computes a grid of points over the interior of a cube in 3D.

DISK_GRID, a MATLAB library which computes a grid of points over the interior of a disk in 2D.

ELLIPSE_GRID, a MATLAB library which computes a grid of points over the interior of an ellipse in 2D.

ELLIPSOID_GRID, a MATLAB library which computes a grid of points over the interior of an ellipsoid in 3D.

HYPERCUBE_GRID, a MATLAB library which computes a grid of points over the interior of a hypercube in M dimensions.

LINE_GRID, a MATLAB library which computes a grid of points over the interior of a line segment in 1D.

POLYGON_GRID, a MATLAB library which generates a grid of points over the interior of a polygon in 2D.

PYRAMID_GRID, a MATLAB library which computes a grid of points over the interior of the unit pyramid in 3D;

SIMPLEX_GRID, a MATLAB library which generates a grid of points over the interior of a simplex in M dimensions.

SPHERE_FIBONACCI_GRID, a MATLAB library which computes a grid of points using the Fibonacci spiral over the surface of a sphere in 3D.

SPHERE_GRID, a MATLAB library which computes a grid of points over the surface of a sphere in 3D.

SPHERE_LLQ_GRID, a MATLAB library which computes a grid of quadrilaterals bounded by latitude and longitude lines over the surface of a sphere in 3D.

SQUARE_GRID, a MATLAB library which computes a grid of points over the interior of a square in 2D.

TETRAHEDRON_GRID, a MATLAB library which computes a grid of points over the interior of a tetrahedron in 3D.

TRIANGLE_GRID, a MATLAB library which computes a grid of points over the interior of a triangle in 2D.

WEDGE_GRID, a MATLAB library which computes a grid of points over the interior of the unit wedge in 3D.

- i4mat_print.m, prints an I4MAT.
- i4mat_print_some.m, prints some of an I4MAT.
- r8vec_print.m, prints an R8VEC.
- sphere_llt_grid_display.m, displays an LLT grid over the surface of a sphere in 3D.
- sphere_llt_grid_line_count.m, counts lines on a latitude/longitude grid.
- sphere_llt_grid_lines.m, produces lines on a latitude/longitude grid.
- sphere_llt_grid_point_count.m, counts points on a latitude/longitude grid.
- sphere_llt_grid_points.m, produces points on a latitude/longitude grid.
- timestamp.m, prints the current YMDHMS date as a time stamp.