makeFITSimHdr: Generate header for FITS image

Description

Function generates the header for a FITS image. It determines much of the header information from the file itself and can merge header information with error checking and removal of conflicting reserved keywords.

Usage

makeFITSimHdr(X, primaryhdu = TRUE, type = "double", c1 = NA, c2 = NA,
bscale = 1, bzero = 0, crpixn = NA, crvaln = NA, cdeltn = NA, ctypen =
NA, cunitn = NA, axDat = NA, header = "")

Arguments

Multi-dimensional numeric data array; see Details.

primaryhdu

Logical: TRUE for stand-alone file, FALSE if subordinate header.

type

Type to write: single or double precision.

Character string comment line for header.

bscale

Global scaling factor, FITS standard meaning.

bzero

Global shift, FITS standard meaning.

crpixn

Vector of reference pixel numbers for axes, FITS standard meaning.

crvaln

Vector of values at reference pixels, FITS standard meaning.

cdeltn

Vector of axis increments per pixel, FITS standard meaning.

ctypen

String vector of descriptive labels for axis, FITS standard meaning.

cunitn

String vector of physical units for axis, FITS standard meaning.

axDat

Data frame with axis data, see details.

header

Optional header of 80-character card images.

Value

String with format and length matching FITS header standard for an image.

References

Hanisch et al., Astron.\ Astrophys. 376, 359-380 (2001)

https://fits.gsfc.nasa.gov/

Examples

Run this code

# NOT RUN {
X <- matrix(1:15, ncol = 3)
# extra header lines (optional)
header <- newKwv('KEYWORD', 'VALUE', 'NOTE') # initialize header
header <- addComment('Add these lines to auto-generated header', header=header)
header <- delKwv('KEYWORD', header=header)  # kill first line
header <- addKwv('test1', 'plot size', header=header)
header <- addKwv('test2', 4294.95397809807, 'number', header=header)
header <- addKwv('test3', 4.29495397809807e50, 'big number', header=header)
# make main header
header <- makeFITSimHdr(X, crpixn = c(1,1), crvaln = c(10, 100),
                        cdeltn = c(8, 2), ctypen = c("Distance", "Time"),
                        cunitn = c("Furlongs", "Fortnights"),
                        header = header)
# finish and close out header
tmp <- closeHdr(header) 
# }