pixelfunc
– Pixelisation related functions¶
conversion from/to sky coordinates¶
pix2ang (nside, ipix[, nest, lonlat]) |
pix2ang : nside,ipix,nest=False,lonlat=False -> theta[rad],phi[rad] (default RING) |
pix2vec (nside, ipix[, nest]) |
pix2vec : nside,ipix,nest=False -> x,y,z (default RING) |
ang2pix (nside, theta, phi[, nest, lonlat]) |
ang2pix : nside,theta[rad],phi[rad],nest=False,lonlat=False -> ipix (default:RING) |
vec2pix (nside, x, y, z[, nest]) |
vec2pix : nside,x,y,z,nest=False -> ipix (default:RING) |
vec2ang (vectors[, lonlat]) |
vec2ang: vectors [x, y, z] -> theta[rad], phi[rad] |
ang2vec (theta, phi[, lonlat]) |
ang2vec : convert angles to 3D position vector |
get_all_neighbours (nside, theta[, phi, …]) |
Return the 8 nearest pixels. |
get_interp_weights (nside, theta[, phi, …]) |
Return the 4 closest pixels on the two rings above and below the location and corresponding weights. |
get_interp_val (m, theta, phi[, nest, lonlat]) |
Return the bi-linear interpolation value of a map using 4 nearest neighbours. |
conversion between NESTED and RING schemes¶
nest2ring (nside, ipix) |
Convert pixel number from NESTED ordering to RING ordering. |
ring2nest (nside, ipix) |
Convert pixel number from RING ordering to NESTED ordering. |
reorder (map_in[, inp, out, r2n, n2r]) |
Reorder a healpix map from RING/NESTED ordering to NESTED/RING |
nside/npix/resolution¶
nside2npix (nside) |
Give the number of pixels for the given nside. |
npix2nside (npix) |
Give the nside parameter for the given number of pixels. |
nside2order (nside) |
Give the resolution order for a given nside. |
order2nside (order) |
Give the nside parameter for the given resolution order. |
nside2resol (nside[, arcmin]) |
Give approximate resolution (pixel size in radian or arcmin) for nside. |
nside2pixarea (nside[, degrees]) |
Give pixel area given nside in square radians or square degrees. |
max_pixrad (nside[, degrees]) |
Maximum angular distance between any pixel center and its corners |
isnsideok (nside[, nest]) |
Returns True if nside is a valid nside parameter, False otherwise. |
isnpixok (npix) |
Return True if npix is a valid value for healpix map size, False otherwise. |
get_map_size (m) |
Returns the npix of a given map (implicit or explicit pixelization). |
get_min_valid_nside (npix) |
Returns the minimum acceptable nside so that npix <= nside2npix(nside). |
get_nside (m) |
Return the nside of the given map. |
maptype (m) |
Describe the type of the map (valid, single, sequence of maps). |
ud_grade (map_in, nside_out[, pess, …]) |
Upgrade or degrade resolution of a map (or list of maps). |
Masking pixels¶
UNSEEN |
Special value used for masked pixels |
mask_bad (m[, badval, rtol, atol]) |
Returns a bool array with True where m is close to badval. |
mask_good (m[, badval, rtol, atol]) |
Returns a bool array with False where m is close to badval. |
ma (m[, badval, rtol, atol, copy]) |
Return map as a masked array, with badval pixels masked. |
Map data manipulation¶
fit_dipole (m[, nest, bad, gal_cut]) |
Fit a dipole and a monopole to the map, excluding bad pixels. |
fit_monopole (m[, nest, bad, gal_cut]) |
Fit a monopole to the map, excluding unseen pixels. |
remove_dipole (m[, nest, bad, gal_cut, …]) |
Fit and subtract the dipole and the monopole from the given map m. |
remove_monopole (m[, nest, bad, gal_cut, …]) |
Fit and subtract the monopole from the given map m. |
get_interp_val (m, theta, phi[, nest, lonlat]) |
Return the bi-linear interpolation value of a map using 4 nearest neighbours. |