CIRCLE_ARC_GRID
Compute Grid Points Along a Circular Arc

CIRCLE_ARC_GRID is a FORTRAN77 library which calculates a grid of points equally spaced over the length of a circle or circular arc in 2D.

Licensing:

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

Languages:

CIRCLE_ARC_GRID is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version and a MATLAB version and a Python version.

Related Programs:

BALL_GRID, a FORTRAN77 library which computes a grid of points over the interior of a ball in 3D.

CUBE_GRID, a FORTRAN77 library which computes a grid of points over the interior of a cube in 3D.

DISK_GRID, a FORTRAN77 library which computes a grid of points over the interior of a disk in 2D.

ELLIPSE_GRID, a FORTRAN77 library which computes a grid of points over the interior of an ellipse in 2D.

ELLIPSOID_GRID, a FORTRAN77 library which computes a grid of points over the interior of an ellipsoide in 3D.

HYPERCUBE_GRID, a FORTRAN77 library which computes a grid of points over the interior of a hypercube in M dimensions.

LINE_GRID, a FORTRAN77 library which computes a grid of points over the interior of a line segment in 1D.

PYRAMID_GRID, a FORTRAN77 library which computes a grid of points over the interior of the unit pyramid in 3D;

SIMPLEX_GRID, a FORTRAN77 library which generates a regular grid of points over the interior of an arbitrary simplex in M dimensions.

SPHERE_GRID, a FORTRAN77 library which provides a number of ways of generating grids of points, or of points and lines, or of points and lines and faces, on the surface of the unit sphere in 3D.

SQUARE_GRID, a FORTRAN77 library which computes a grid of points over the interior of a square in 2D.

TETRAHEDRON_GRID, a FORTRAN77 library which computes a grid of points over the interior of a tetrahedron in 3D.

TRIANGLE_GRID, a FORTRAN77 library which computes a triangular grid of points.

WEDGE_GRID, a FORTRAN77 library which computes a grid of points over the interior of the unit wedge in 3D.

Source Code:

• circle_arc_grid.f, the source code.
• circle_arc_grid.sh, commands to compile the source code.

Examples and Tests:

• circle_arc_grid_prb.f, a sample calling program.
• circle_arc_grid_prb.sh, commands to compile and run the calling program.
• circle_arc_grid_prb_output.txt, the output file.

ARC is a set of 10 equally spaced points from 0 to 90 degrees, on a circle of radius 2 centered at (5,5).

• arc.txt, the data.
• arc.png, an image of the points.

PENTAGON is a set of 6(!) equally spaced points from 0 to 360 degrees. This is the easiest way to get a pentagon, but you should really edit the file and remove the last point, since it repeats the first one. The alternative is to specify that the angles range from 0 to 288 degrees!

• pentagon.txt, the data
• pentagon.png, an image of the points.

List of Routines:

• CIRCLE_ARC_GRID computes grid points along a circular arc.
• GET_UNIT returns a free FORTRAN unit number.
• R82VEC_PRINT_PART prints "part" of an R82VEC.
• R8MAT_WRITE writes an R8MAT file.
• TIMESTAMP prints the current YMDHMS date as a time stamp.

You can go up one level to the FORTRAN77 source codes.