R help - Oct 2013 - R: Optional argument to be used in a subset function

I'm writing a function that needs an optional variable. If the variable is
given, then a subset must be made using that variable, but if the variable
is not given the subset must be done using all the values for that variable
(ignoring that variable).

Something like this:

*band <- function(file, fruit = "apple", optional=TRUE) {*

*data <- read.csv(file)*

*a <- nrow(subset(data, 'Column 1' == fruit & 'Column
2'=="hot" & 'Column 3'=optional))*

*b <- nrow(subset(data,'Column 1' == fruit & 'Column
2'=="cold" & 'Column 3'=optional)) *

*z <- a+b*

* print(z)*

* }*

What I need is that the function *band("file","orange")*, 
subset the data
frame using all possible values for Column 3 but is not doing it.

All ideas are welcome.

Thanks.


David Mora

	[[alternative HTML version deleted]]

On 24-10-2013, at 16:15, David Mora <dmvxic at gmail.com> wrote:
> I'm writing a function that needs an optional variable. If the variable
is
> given, then a subset must be made using that variable, but if the variable
> is not given the subset must be done using all the values for that variable
> (ignoring that variable).
> 
> Something like this:
> 
> *band <- function(file, fruit = "apple", optional=TRUE) {*
> 
> *data <- read.csv(file)*
> 
> *a <- nrow(subset(data, 'Column 1' == fruit & 'Column
2'=="hot" & 'Column 3'=> optional))*
> 
> *b <- nrow(subset(data,'Column 1' == fruit & 'Column
2'=="cold" & 'Column 3'=> optional)) *
> 
> *z <- a+b*
> 
> * print(z)*
> 
> * }*
> 
> What I need is that the function
*band("file","orange")*,  subset the data
> frame using all possible values for Column 3 but is not doing it.
> 
> All ideas are welcome.
> 
> Thanks.
> 
> 
> David Mora
> 
> 	[[alternative HTML version deleted]]
> 
Please do not post in HTML.
And make stuff bold: in plain text it is converted to things like this:

* }*

which nonsense for R.

Berend
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

Sorry for the html code:

I'm writing a function that needs an optional variable. If the variable is
given, then a subset must be made using that variable, but if the variable
is not given the subset must be done using all the values for that variable
(ignoring that variable).

Something like this:

band <- function(file, fruit = "apple", optional=TRUE) {

data <- read.csv(file)

a <- nrow(subset(data, 'Column 1' == fruit & 'Column
2'=="hot" & 'Column
3'== optional))

b <- nrow(subset(data,'Column 1' == fruit & 'Column
2'=="cold" & 'Column
3'== optional))

z <- a+b

 print(z)

 }
*
*
What I need is that the function band("file","orange"), 
subset the data
frame using all possible values for Column 3 but is not doing it.

All ideas are welcome.

Thanks.

David Mora


On Thu, Oct 24, 2013 at 8:15 AM, David Mora <dmvxic@gmail.com> wrote:
> I'm writing a function that needs an optional variable. If the variable
is
> given, then a subset must be made using that variable, but if the variable
> is not given the subset must be done using all the values for that variable
> (ignoring that variable).
>
> Something like this:
>
> *band <- function(file, fruit = "apple", optional=TRUE) {*
>
> *data <- read.csv(file)*
>
> *a <- nrow(subset(data, 'Column 1' == fruit & 'Column
2'=="hot" & 'Column
> 3'== optional))*
>
> *b <- nrow(subset(data,'Column 1' == fruit & 'Column
2'=="cold" & 'Column
> 3'== optional)) *
>
> *z <- a+b*
>
> * print(z)*
>
> * }*
>
> What I need is that the function
*band("file","orange")*,  subset the
> data frame using all possible values for Column 3 but is not doing it.
>
> All ideas are welcome.
>
> Thanks.
>
>
> David Mora
>
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