[R] warning on generic function when building R package

[Duncan Murdoch]

On 19/10/2015 3:50 PM, carol white wrote:
> Thanks Murdoch.
> 
> defining
> plot.func<- function(x=x.init, y=y.init, arg3, arg4, "title", col, arg5)
> 
> and if plot doesn't take the exact parameters of plot.func but modified
> of these parameters
> plot(x=x.pt,y=y.pt,xlim = c(0, 10), ylim = c(0,1), xlab= "xlab",
> ylab="ylab", main = "title", col = col,type = "l")
> 
> then, how to define and invoke to be consisent?

I don't really understand your question, but this is all about the
function header for plot.func, not the call you make to plot().  You
need to name the first argument as "x", you need to include "..." as an
open argument, and you need a legal header.  So this would be okay:


plot.func<- function(x=x.init, y=y.init, arg3, arg4,
                     main = "title", # can't skip the arg name
                     col, arg5,
                     ...)  {          # can't skip the dots

Duncan Murdoch

> 
> Regards,
> 
> On Monday, October 19, 2015 7:45 PM, Duncan Murdoch
> <murdoch.duncan at gmail.com> wrote:
> 
> 
> On 19/10/2015 1:29 PM, carol white via R-help wrote:
> 
>> Hi,I have invoked plot in a function (plot.func) as follows but when I
> check the built package, I get a warning:
>> plot(x.pt,y.pt,xlim = c(0, 10), ylim = c(0,1), xlab= "xlab",
> ylab="ylab", main = "title", col = col,type = "l")
>> R CMD check my.package
>> checking S3 generic/method consistency ... WARNING
>> plot:
>>  function(x, ...)
>> plot.func:
>>  function(x.pt, y.pt, arg3, arg4, "title", col, arg5)
>>
>> See section ‘Generic functions and methods’ in the ‘Writing R
>> Extensions’ manual.
>> Which plot argument is illegitimate or missing and how to eliminate
> the warning?
> 
> 
> The first argument to plot.func needs to be called "x" if you want to
> use it as a method.  Method signatures need to be consistent with the
> generic signature.
> 
> Duncan Murdoch
> 
> 
> 
>