writeANALYZE

This function saves an Analyze-class object to a single binary file in Analyze format.

# S4 method for anlz
writeANALYZE(
  aim,
  filename,
  gzipped = TRUE,
  verbose = FALSE,
  warn = -1,
  compression = 6
)

Arguments

aim	is an object of class `anlz`.
filename	is the path and file name to save the Analyze file pair (.hdr,img) without the suffixes.
gzipped	is a character string that enables exportation of compressed (.gz) files (default = `TRUE`).
verbose	is a logical variable (default = `FALSE`) that allows text-based feedback during execution of the function.
warn	is a number to regulate the display of warnings (default = -1). See `options` for more details.
compression	The amount of compression to be applied when writing a file when `gzipped = TRUE`

Value

Nothing.

Details

The writeANALYZE function utilizes the internal writeBin and writeChar command to write information to a binary file.

Methods

object = "anlz": Write ANALYZE volume to disk.

References

Analyze 7.5
http://eeg.sourceforge.net/ANALYZE75.pdf

Author

Brandon Whitcher bwhitcher@gmail.com

Examples


norm <- dnorm(seq(-5, 5, length=32), sd=2)
norm <- (norm-min(norm)) / max(norm-min(norm))
img <- outer(outer(norm, norm), norm)
img <- round(255*img)
img[17:32,,] <- 255 - img[17:32,,]
img.anlz <- anlz(img) # create Analyze object

fname = file.path(tempdir(), "test-anlz-image-uint8")

writeANALYZE(img.anlz, fname, verbose=TRUE)
#>   dims = 32 32 32
## These files should be viewable in, for example, FSLview
## Make sure you adjust the min/max values for proper visualization
data <- readANALYZE(fname, verbose=TRUE)
#>   fname = /tmp/RtmpfdMn90/test-anlz-image-uint8
#>   files = /tmp/RtmpfdMn90/test-anlz-image-uint8.{hdr.gz,img.gz}
#>   hdr   = /tmp/RtmpfdMn90/test-anlz-image-uint8.hdr.gz
#>   img   = /tmp/RtmpfdMn90/test-anlz-image-uint8.img.gz
image(img.anlz, oma=rep(2,4), bg="white")
image(data, oma=rep(2,4), bg="white")

abs.err <- abs(data - img.anlz)
image(as(abs.err, "anlz"), zlim=range(img.anlz), oma=rep(2,4), bg="white")


if (FALSE) {
## Loop through all possible data types
datatypes <- list(code=c(2, 4, 8, 16, 64),
                  name=c("uint8", "int16", "int32", "float", "double"))
equal <- vector("list")
for (i in 1:length(datatypes$code)) {
  fname <- paste("test-anlz-image-", datatypes$name[i], sep="")
  fname = file.path(tempdir(), fname)
  rm(img.anlz)
  img.anlz <- anlz(img, datatype=datatypes$code[i])
  writeANALYZE(img.anlz, fname)
  equal[[i]] <- all(readANALYZE(fname) == img)
}
names(equal) <- datatypes$name
unlist(equal)
}