toasty.toast Module

Computations for the TOAST projection scheme and tile pyramid format.

For all TOAST maps, the north pole is in the dead center of the virtual image square, the south pole is at all four of its corners, and the equator is a diamond connecting the midpoints of the four sides of the square. (See Figure 3 of McGlynn+ 2019, DOI:10.3847/1538-4365/aaf79e).

For TOAST maps of the sky, the line of RA (lon) = 0 in the northern hemisphere extends from the center of the square to the right, as in the Figure 3 mentioned above. The RA = 90 line goes from the center up, and so on counter-clockwise around the square.

For TOAST planetary maps, the lon = 0 line in the northern hemisphere extends from the center of the square to the left. The lon = 90 line extends downwards, and increasing longitude results in counter-clockwise motion around the square as for sky maps. In other words, the longitudinal orientation is rotated by 180 degrees.

Functions

count_tiles_matching_filter(depth, filter[, ...])	Count the number of tiles matching a filter.
create_single_tile(pos[, coordsys])	Create a single TOAST tile.
generate_tiles(depth[, bottom_only, coordsys])	Generate a pyramid of TOAST tiles in deepest-first order.
generate_tiles_filtered(depth, filter[, ...])	Generate a pyramid of TOAST tiles in deepest-first order, filtering out subtrees.
sample_layer(pio, sampler, depth[, ...])	Generate a layer of the TOAST tile pyramid through direct sampling.
sample_layer_filtered(pio, tile_filter, ...)	Populate a subset of a layer of the TOAST tile pyramid through direct sampling.
toast_pixel_for_point(depth, lat, lon[, ...])	Identify the pixel within a TOAST tile at a given depth that contains the given point.
toast_tile_area(tile)	Calculate the area of a TOAST tile in steradians.
toast_tile_for_point(depth, lat, lon[, coordsys])	Identify the TOAST tile at a given depth that contains the given point.
toast_tile_get_coords(tile)	Get the coordinates of the pixel centers of a TOAST Tile.

Classes

Tile(pos, corners, increasing)
ToastCoordinateSystem(value)	Different TOAST coordinate systems that are in use.
ToastSampler(pio, sampler, clobber[, format])	A utility for performing TOAST sampling on a Pyramid.