Re: [Gretl-devel] problem with pointerized bundle member
Am 29.09.2015 um 20:32 schrieb Sven Schreiber:
Am 29.09.2015 um 18:48 schrieb Allin Cottrell:
> (2) When a matrix is used as an argument to a user-defined
function,
> there are two ways to ensure it is "passed along" to the function rather
> than being copied: give the argument in "pointer" form, or
> mark the argument as "const".
>
> So consider a modified version of your script:
>
> <hansl>
> function void hey(const matrix hu)
> print "hey"
> end function
>
> bundle bbb
> bbb.in = ones(2,2)
> hey(bbb.in)
> </hansl>
>
> The matrix bbb.in will not be copied in this case. But if we removed the
> const flag to the "hu" argument it would get copied on entry to the
> function.
>
Ok, very informative. Thanks!
A follow-up on this: I just noticed that example 13.1 in the manual has
this function header:
"function scalar b(const matrix *X)"
From what you explained here, the pointer form in this example would be
redundant, right?
thanks,
sven