Limiter Gird File

Table of Contents

• Introduction
• Input Configuation
  • Keywords
  • Example File
• Command Line Arguments

Introduction

LGRID is a code to precompute the distance from a grid point to the closest point on a limiter. Limiters are specified as a series of line segments in a counter clockwise fasion. That is a polygon with vertices ordered in a counter clockwise will have the inside of the polygon represent the interior. Clockwise ordering will have the outside of the polygon represent the interior.

Input Configuation

All limiters are defined using the same format. A key word, the number of phi planes the limiter surface is associated with, a list of phi values and then a list of r z segment positions terminated by a end_limiter keyword.

keyword
num_phi
phi1(REAL) phi2(REAL) ... phiN(REAL)
r1(REAL) z1(REAL)
r2(REAL) z2(REAL)
...
rM(REAL) zM(REAL)
end_limiter


Keywords

new_limiter_deg	A limiter at phi angles specified in degrees.
new_limiter_rad	A limiter at phi angles specified in radians.
end_limiter	End of the limiter.

Example File

new_limiter_deg
3
10.0 50.0 175.0
0.5 -0.25
1.0 -0.25
1.0  0.25
0.5  0.25
end_limiter

Command Line Arguments

LGRID is run with the following command.

lgrid filename r0 dr numr z0 dz numz

filename	Path to file containing the limiter configuation.
r0	Starting radial grid position.
dr	Radial grid width.
numr	Number of radial grid points.
z0	Starting vertical grid position.
dz	Vertical grid width.
numz	Number of vertical grid points.