FEXPest : glimstep: no visible global function definition for ‘update’
FEXPest : glimstep: no visible global function definition for
  ‘as.formula’
FEXPest : glimstep: no visible global function definition for ‘glm’
FEXPest : glimstep: no visible global function definition for ‘Gamma’
Qeta: no visible global function definition for ‘pnorm’
WhittleEst: no visible global function definition for ‘sd’
WhittleEst: no visible global function definition for ‘optimize’
WhittleEst: no visible global function definition for ‘optim’
WhittleEst: no visible global function definition for ‘pnorm’
lines.FEXP: no visible global function definition for ‘lines’
lines.WhittleEst: no visible global function definition for ‘lines’
linesSpec: no visible global function definition for ‘lines’
llplot: no visible global function definition for ‘plot’
llplot: no visible global function definition for ‘lines’
lxplot: no visible global function definition for ‘plot’
lxplot: no visible global function definition for ‘lines’
per: no visible global function definition for ‘fft’
plot.FEXP: no visible global function definition for ‘plot’
plot.FEXP: no visible global function definition for ‘lines’
plot.FEXP: no visible global function definition for ‘mtext’
plot.WhittleEst: no visible global function definition for ‘plot’
plot.WhittleEst: no visible global function definition for ‘lines’
print.FEXP: no visible global function definition for ‘printCoefmat’
print.FEXP: no visible global function definition for ‘str’
print.WhittleEst: no visible global function definition for
  ‘printCoefmat’
print.WhittleEst: no visible global function definition for ‘str’
simGauss: no visible global function definition for ‘fft’
simGauss: no visible global function definition for ‘rnorm’
simGauss: no visible global function definition for ‘ts’
Undefined global functions or variables:
  Gamma as.formula fft glm lines mtext optim optimize plot pnorm
  printCoefmat rnorm sd str ts update
Consider adding
  importFrom("graphics", "lines", "mtext", "plot")
  importFrom("stats", "Gamma", "as.formula", "fft", "glm", "optim",
             "optimize", "pnorm", "printCoefmat", "rnorm", "sd", "ts",
             "update")
  importFrom("utils", "str")
to your NAMESPACE file.