# Functions by Category

MEALPix Toolbox Version 3.0 21 February 2011

## Contents

- Coordinate Conversions
- Coordinate-Pixel Conversions
- Functions on the sphere
- Map Statistics
- Pixel Indexing Conversions
- Pixel Topology
- Plotting
- Resolution Relations

## Coordinate Conversions

- `ang2vec` - Convert from spherical to cartesian coordinates
- `vec2ang` - Convert cartesian direction vector to position angle on sphere

## Coordinate-Pixel Conversions

- `ang2pix` - Convert spherical coordinate location to HEALPix pixel number
- `pix2ang` - Find spherical coordinate location of HEALPix pixels
- `pix2vec` - Convert HEALPix pixel numbers to (x,y,z) unit vector
- `ring2z` - Find HEALPix ring number corresponding to a given z coordinate
- `vec2pix` - Convert cartesian direction vectors to MEALPix pixel numbers
- `z2ring` - Find HEALPix ring numbers from direction vector z coordinate

## Functions on the sphere

- `alm2pix` - Evaluate spherical harmonic function expansion on HEALPix pixels
- `angDist` - Computes angular distance on the unit sphere
- `pix2alm` - Find spherical harmonic decomposition of function on sphere
- `ylm` - returns spherical harmonic basis on the HEALPix sphere

## Map Statistics

- `alm2spec` - valuate angular power spectral density
- `hpStat` - Compute descriptive statistics of a pixel value list

## Pixel Indexing Conversions

- `nest2ring` - Convert MEALPix pixel numbers from nest to ring indexing
- `ring2nest` - Convert MEALPix pixel numbers from ring to nest indexing

## Pixel Topology

- `corners` - Find pixel corners
- `inRing` - return pixels in ring or ring section
- `pix2xy` - Find pixel cartesian face coordinates
- `queryDisc` - Find all pixels whose centers are within a specified disc
- `xy2pix` - gives the pixel number ipix (NESTED) of ix, iy and face_num

## Plotting

- `hp3d` - Plots a HEALPix dataset on a 3D sphere

## Resolution Relations

- `nPix2nSide` - Convert number of pixels to number of facet side subdivisions
- `nSide2nPix` - Convert resolution parameter to number of pixels
- `nSide2res` - Calculates angular resolution of a HEALPix map in arcsec
- `res2nSide` - Finds minimum base pixel sub-division for required resolution

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