Assigns fibers to galaxy targets in the sky. It takes as inputs a set of galaxies and fibers and returns a match fiber-galaxy. The fibers are arranged in an hexagonal tile.

Python

• The code assumes a flat sky.
• Option for writing to disk the match fiber-galaxy has to be implemented
• Include the priority information of different galaxy populations into the matching routine.
• Write tests for quality assessment.
• Implement Simulated Annealing.

Required galaxy catalog input: Is an ASCII file with four columns separated by spaces. Each line corresponding to a galaxy with:

• unique galaxy_ID in the sky (scalar, int)
• galaxy type (scalar, int). Identifies three kinds of galaxies: ELG, LRG, QSO.
• ra (scalar, float) position in degrees
• dec (scalar, float) position in degrees

Required inputs to construct the fibers:

• fiber_pitch (scalar, float) default 0.01. Distance between fibers in degrees. Same number for all fibers.
• Ndiameter (scalar, integer) default 73. Number of fibers along the major axis in a hexagonal tile
• center_x (scalar, float) default 0.0. Position of the hexagon's center in the ra-direction. In degrees
• center_y (scalar, float) default 0.0. Position of the hexagon's center in the dec-direction. In degrees.

Required input to feed the allocation routine:

• tile_ID (scalar, integer) default 1. A unique ID during the survey. Identifies the tile that triggered this instance of fiber allocation. The module will take as input a whole array of tile_ids, one for each galaxy (or -1).
• visit_ID (scalar, integer) default 1. A unique ID for each tile. Identifies the number of times that a particular tile_ID has been observed. It is the number of times that a tile has been visited
• patrol_radius (scalar, float) default 0.01. patrol radius of each fiber. It is the same for all fibers. In degrees.
• exclusion_radius (scalar, float) default 0.0. Minimum separation between the centers of two fibers are allowed to have before having a collision. In degrees.
• fiber_size (scalar, float) default 0.0. Diameter of the fibers. The exclusion_radius parameter should be equal or larger than half the fiber_size. It is the same for all fibers. In degrees.

Data that is produced inside the routine as initialization: A list of fibers with the following information:

• A unique fiber ID (scalar, int)
• The unperturbed ra-dec coordinates (scalar, floats). In degrees.

Data that is produced inside the routine after the allocation is completed. For each fiber:

• The corresponding galaxy_ID that the fiber will observe (scalar, int).
• The value is -1 if the fiber is free.
• The perturbed positions in ra-dec coordinates (scalar, floats) after the allocation. They correspond to the galaxy's coordinates allocated to this fiber.

Outputs The output is a list of galaxies with 7 columns:

• unique galaxy_ID in the sky (scalar, int)
• galaxy type (scalar, int). Corresponds to ELG, LRG, QSO.
• ra (scalar float). Same as input.
• dec (scalar, float). Same as input.
• tile_ID (scalar, int). Sames as input if galaxy was allocated. -1 if not.
• visit_ID (scalar, int). Same as input if galaxy was allocated. -1 if not.
• fiber_ID (scalar, int). fiber_ID of the fiber allocated to it. -1 it none.

• class FiberSet
• class MockGalaxyCatalog
• function close_match_xy
• function reset_fiber_collisions
• function make_fiber_allocation

• numpy
• sys

Currently the code can be executed as

# Creates a set of fibers
fibers = FiberSet(Ndiameter=73, fiber_pitch=0.1)

# Creates a set of galaxies
gals = MockGalaxyCatalog(Ngalaxies=50000, radius_fov=fibers.radius,priority_levels=3) 

# Runs the fiber allocation
make_fiber_allocation(fibers, gals, tile_visit_ID=340)