[R-sig-finance] Backtest trading strategies

[Gabor Grothendieck]

On 11/26/05, paul sorenson <sourceforge at metrak.com> wrote:
> Gabor Grothendieck wrote:
> > On 11/26/05, Rob Steele <rfin.20.phftt at xoxy.net> wrote:
> >
> >>Neuro LeSuperHéros wrote:
> >>
> >>>Hello,
> >>>
> >>>I understand the utility of MySQL for data storage.  But why is Python
> >>>essential?  What does it do that R can't do for system
> >>>creation/calculation?
> >>>
> >>>Thanks
> >>
> >>
> >>Python is great for parsing data from wherever you get it and populating
> >>databases.  MySQL is ideal for the write-once-read-thereafter scenario
> >>that research implies.  You can use R for the initial data marshaling
> >>if you'd rather not learn another language but Python seems like a
> >>better fit for that sort of thing.  It's a scripting language that
> >>integrates more naturally into its host environment.  For analysis and
> >>visualization however, R absolutely rules.
> >
> >
> > I don't use MySQL so won't comment on that part but for parsing
> > data I have found R to have everything I need.  I used to use perl
> > but now use R exclusively.    R's string manipulation includes
> > regular expressions and the vector processing often simplifies
> > string manipulation by eliminating loops over lines or vectors
> > of strings.
> >
> > To me its much easier to maintain code if its all in one language and
> > moving to R has enabled me to replace a bunch of perl, batch files
> > and other statistical software with R which really helps clean it
> > all up.  (Actually I still have some Windows batch files, see
> > http://cran.r-project.org/contrib/extra/batchfiles/, but they are only
> > for generic configuration utilities and nothing specific to any application.)
>
> Each to their own I guess.  I happen to be much more familiar with
> Python than R and often use it to grab data in various formats which R
> won't read.  I wouldn't dream of using an MSDOS batch file.  As I learn
> more about R, I tend to do more in it but I couldn't imagine myself
> parsing dodgy HTML, for example, with it.

Actually I use R for parsing HTML and for parsing XML too.  I do
agree by Rob that it would be nice if R worked better with shells
and also wish I could write small self contained executables in R
like one can in tcl and Python.