# MEALPix for the HEALPix User

## Contents

- MEALPix function names are derived from their HEALPix counterparts.
- MEALPix functions accept array arguments
- MEALPix indexes pixels from 1

## MEALPix function names are derived from their HEALPix counterparts.

MEALPix functions are typically camel-cased (e.g., `angDist`, or `nSide2nPix`). Underscores in HEALPix names are dropped in the conversion to MEALPix names.

## MEALPix functions accept array arguments

MEALPix functions exploit Matlab(tm)'s vectorization facilities to allow for the processing of arrays of pixels, direction vectors and position angle vectors via a single function call. For example, the MEALPix implementation of `angDist` accepts mixed arrays of cartesian direction vectors, angular position vectors, and ring or nest indexed pixels for either argument.

## MEALPix indexes pixels from 1

HEALPix pixels are indexed from 0. In keeping with the Matlab standard MEALPix pixels are indexed from 1. MEALPix pixels are indexed from 1: i.e., MEALPix pixel number n corresponds to HEALPix pixel number n-1.

Copyright 2010-2011 Lee Samuel Finn. Terms of Use.