corners
Find pixel corners
Contents
Syntax
xyz = corners(nSide,nPix,'Param1',Value1,...);
Input Arguments
nSide HEALPix resolution parameter nPix (optional) pixel list. Default all pixels.
Param Value
'nest' nested indexing (true | {false})Return Arguments
xyz size(nPix) cell array of [3,1] cartesian vector pixel corner
locationsExample:
nSide = 2^2; % Corners for all 48 nSide=4 pixels in ring-indexed order xyzR = corners(nSide); size(xyzR) xyzR{1} xyzR{end-1} nPix = randi(nSide2nPix(nSide), 3, 4); % Corners for an assortment of pixels in nested index order xyzN = corners(nSide,nPix,'nest',true); % Convert to pixel list to ring indexing r = xyzR{nest2ring(nSide,nPix(2,3))} % Corners for same pixels requested via ring indexing n = xyzN{2,3} % Compare all(r == n)
ans =
1 192
ans =
0 0.2031 0.2826 0.0000
0 0 0.2826 0.2031
1.0000 0.9792 0.9167 0.9792
ans =
-0.2826 -0.2031 0 -0.0000
-0.2826 0.0000 0 -0.2031
-0.9167 -0.9792 -1.0000 -0.9792
r =
0.5478 0.7071 0.5478 0.3827
0.8198 0.7071 0.8198 0.9239
0.1667 0 -0.1667 0
n =
0.5478 0.7071 0.5478 0.3827
0.8198 0.7071 0.8198 0.9239
0.1667 0 -0.1667 0
ans =
1 1 1 1
Copyright 2010-2011 Lee Samuel Finn. Terms of Use.