zipfR (version 0.6-5)

read.spc: Loading and Saving Frequency Spectra (zipfR)

Description

read.spc loads frequency spectrum from .spc file

write.spc saves frequency spectrum object in .spc file

Usage

read.spc(file)
  write.spc(spc, file)

Arguments

file

character string specifying the pathname of a disk file. See section "Format" for a description of the required file format

spc

a frequency spectrum, i.e. an object of class spc

Value

• read.spc returns an object of class spc (see the spc manpage for details)

Details

The .spc file format does not store the values of N, V and VV explicitly. Therefore, incomplete frequency spectra and expected spectra with variances cannot be fully reconstructed from disk files. Saving such frequency spectra (or loading a spectrum with variance data) will trigger corresponding warnings.

See Also

See the spc manpage for details on spc objects. See read.tfl and read.vgc for import/export of other data structures.

Examples

## examples will not be run during package compilation
## since they would require accessing and writing to
## external files

## load Italian ultra- data
## and write corresponding spectrum to external text file
data(ItaUltra.spc)
write.spc(ItaUltra.spc,"ultra.spc")
## now ultra.spc is a text file with columns m and Vm

## we ready it back in
New.spc <- read.spc("ultra.spc")

## same spectrum as ItaUltra.spc, compare:
summary(New.spc)
summary(ItaUltra.spc)

## DON'T do the following, incomplete spectrum will not be
## restored properly!!!
zm <- lnre("zm",ItaUltra.spc) # estimate model
zm.spc <- lnre.spc(zm,N(zm)) # incomplete spectrum from model
write.spc(zm.spc,"var.spc") # warnings
bad.spc <- read.spc("/Users/baroni/Desktop/var.spc")
## latter is DIFFERENT from zm.spc!!!