[R] avoiding reinstall already installed *package*

[Martin Maechler]

{ I've modified the subject; I can't stand it hitting square into
  my face ... }

>>>>> "mr" == milton ruser <milton.ruser at gmail.com>
>>>>>     on Tue, 18 May 2010 12:36:23 -0300 writes:

    mr> Dear R-experts,
    mr> I am installing new libraries using
    mr> install.packages("ggplot2",dependencies=T).
    mr> But I perceive that many dependencies are already installed. As I am using
    mr> a low-band internet, how can avoid reinstall installed libraries?

There's no problem with installed libraries, as ... 
they DO NOT EXIST.

These are *PACKAGES* !
Why do you think are you talking about the function

 install.packages()  ????
         ^^^^^^^^

---
To answer the question you did want to ask:

Do not be afraid:  Depedencies are only installed when needed,
i.e., no package will be downloaded and installed if it already
is there.

Martin Maechler, ETH Zurich

    mr> cheers

    mr> milton

    mr> [[alternative HTML version deleted]]
    	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
(another thing you should learn to avoid, please)