as.CMBDataFrame: Convert objects to 'CMBDataFrame'
In rcosmo: Cosmic Microwave Background Data Analysis

Description Usage Arguments Value Examples

Safely converts a data.frame to a CMBDataFrame. The rows of the data.frame are assumed to be in the HEALPix order given by ordering, and at the HEALPix resolution given by nside. Coordinates, if present, are assumed to correspond to HEALPix pixel centers. The coordinates must be named either x,y,z (cartesian) or theta, phi (spherical colatitude and longitude respectively). If df is a HPDataFrame then it is possible that df has attribute healpixCentered = TRUE, in which case as.CMBDataFrame will perform HEALPix centering of coordinates.

1	as.CMBDataFrame(df, ordering, nside, spix, drop.coords = FALSE)

`df`	Any `data.frame` or `HPDataFrame` whose rows are in HEALPix order
`ordering`	character string that specifies the ordering scheme ("ring" or "nested")
`nside`	an integer 2^k that specifies the Nside (resolution) HEALPix parameter
`spix`	an integer vector that specifies the HEALPix pixel index corresponding to each row of `df`. If `spix` is left blank and `df` is a `data.frame`, then `df` is assumed to contain data for every pixel at resolution parameter `nside` (the full sky). In other words, in this case, the number of rows of `df` must be equal to 12*nside^2. However, if `spix` is left blank and `df` is a `CMBDataFrame`, then `spix` is set equal to `pix(df)`
`drop.coords`	A logical. If `df` is a `HPDataFrame` then it is possible that `df` has attribute `healpixCentered = TRUE`, in which case `as.CMBDataFrame` will perform HEALPix centering of coordinates. If `drop.coords = TRUE` then this will be done by dropping existing coordinates entirely (quicker) to rely only on HEALPix pixel indices. Otherwise if `drop.coords = FALSE` this will be done by replacing existing coordinates with locations of HEALPix pixel centers.

A CMBDataFrame

## Example 1: Create df with no coords, then create CMBDataFrames cmbdf and
## df2 with spherical coords

df <- data.frame(I=rnorm(12))
df

cmbdf <- as.CMBDataFrame(df,ordering= "ring", nside=1)
summary(cmbdf)
pix(cmbdf)
coords(cmbdf)

df2 <- coords(cmbdf, new.coords = "spherical")
df2

## Example 2: Create CMBDataFrames for first 10 Healpix centers

df <- data.frame(I=rnorm(10))
df
cmbdf <- as.CMBDataFrame(df,ordering= "ring", nside=2, spix=1:10)
summary(cmbdf)
pix(cmbdf)