Problem with dyn.load...or else...

Marie-H?l?ne Ouellette wrote:

Hi everybody,
I'm working on Mac OS X and R-2.1.0 (by the way, sorry for the multiple 
emails last time, had a technical problem, and thanks for the 
constructive comments.)
I have a .R function which calls a .C function.  The R function's name is 
K_MEANSR.R and the other is K_MEANSC.C.
I compile it with 'R CMD SHLIB K_MEANSC.C' in the terminal.  I get both 
.so and .o files.
I use the function

 > dyn.load ('K_MEANSC.so')

with no error.  We can, I believe, see here that it is loaded:

 > getLoadedDLLs()

Filename
base base
grDevices 
/Library/Frameworks/R.framework/Resources/library/grDevices/libs/grDevices.so
stats /Library/Frameworks/R.framework/Resources/library/stats/libs/stats.so
methods 
/Library/Frameworks/R.framework/Resources/library/methods/libs/methods.so
K_MEANSC 
/Users/admin/Desktop/Marie/Marie_labo_29_juin/K-means_versions/MAC/K_MEANSC.so
R_X11 /Library/Frameworks/R.framework/Resources/modules/R_X11.so
           Dynamic.Lookup
base               FALSE
grDevices          FALSE
stats              FALSE
methods            FALSE
K_MEANSC            TRUE
R_X11               TRUE

I then source the R code:

 > source(file.choose())

Construct a matrix that I will use for the analysis:

 > tab<-c(1,1,3,4,6,6,3,5,7,67,5,6,65,3,5,1,5,42,3,567,6,4,7,7)
 > tab<-matrix(tab,6,4)

And try to use the function:

 > K_MEANSR(tab,centers=c(2,4))

[1] "AA"
[1] "AAA"
[1] "A"
[1] "B"
Error in .C("K_MEANSC", xrows = as.integer(xrows), xcols = 
as.integer(xcols),  :
         "C" function name not in load table
Everything that is printed on the screen is correct, but why does it says 
that 'K_MEANSC' function is not in load table??? It then just stops at 
that stage of the .R function.

What does your declaration of the function look like in the K_MEANSC.C 
file?  R needs to know the name of the exported function, not the name of 
the .so file.

Duncan Murdoch