HEALPix in Megapixels – Andrea Zonca

How many megapixels is a HEALPix map?

!pip install healpy

Collecting healpy
  Downloading healpy-1.16.6-cp310-cp310-manylinux_2_17_x86_64.manylinux2014_x86_64.whl (24.5 MB)
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Installing collected packages: healpy
Successfully installed healpy-1.16.6

import healpy as hp

megapixels = []
for nside_power in range(8, 15):
  nside = 2**nside_power
  megapixels.append((nside, hp.nside2npix(nside)/1e6))

megapixels

[(256, 0.786432),
 (512, 3.145728),
 (1024, 12.582912),
 (2048, 50.331648),
 (4096, 201.326592),
 (8192, 805.306368),
 (16384, 3221.225472)]

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