R help - Mar 2012 - Converting a string vector with names to a numeric vector with names

Not paying close attention to detail, I entered the equivalent of

pstr<-c("b1=200", "b2=50", "b3=0.3")

when what I wanted was

pnum<-c(b1=200, b2=50, b3=0.3)

There was a list thread in 2010 that shows how to deal with un-named vectors,
but the same
lapply solution doesn't seem to work here i.e.,

pnum<-lapply(pstr, as.numeric)

or similar vapply version. The names and = signs seem to mess things up.

This is clearly not critical, but it would be nice to know an appropriate
transformation.

JN

On Thu, Mar 1, 2012 at 12:28 PM, John C Nash <nashjc at uottawa.ca>
wrote:
> Not paying close attention to detail, I entered the equivalent of
>
> pstr<-c("b1=200", "b2=50", "b3=0.3")
>
> when what I wanted was
>
> pnum<-c(b1=200, b2=50, b3=0.3)
>
> There was a list thread in 2010 that shows how to deal with un-named
vectors, but the same
> lapply solution doesn't seem to work here i.e.,
>
> pnum<-lapply(pstr, as.numeric)
>
> or similar vapply version. The names and = signs seem to mess things up.
>
> This is clearly not critical, but it would be nice to know an appropriate
transformation.
Here's one:

split = sapply(strsplit(pstr, split = "="), I);

pnum = as.numeric(split[2, ]);
names(pnum) = split[1, ];
> pnum
   b1    b2    b3
200.0  50.0   0.3

HTH

Peter

On Thu, Mar 01, 2012 at 03:28:31PM -0500, John C Nash
wrote:
> Not paying close attention to detail, I entered the equivalent of
> 
> pstr<-c("b1=200", "b2=50", "b3=0.3")
> 
> when what I wanted was
> 
> pnum<-c(b1=200, b2=50, b3=0.3)
> 
> There was a list thread in 2010 that shows how to deal with un-named
vectors, but the same
> lapply solution doesn't seem to work here i.e.,
> 
> pnum<-lapply(pstr, as.numeric)
> 
> or similar vapply version. The names and = signs seem to mess things up.
> 
> This is clearly not critical, but it would be nice to know an appropriate
transformation.
Hi.

Try the following.

  mat <- sapply(strsplit(pstr, "="), identity)
  x <- as.numeric(mat[2, ])
  names(x) <- mat[1, ]
  x

     b1    b2    b3 
  200.0  50.0   0.3 
 
Hope this helps.

Petr Savicky.

Gotta love R.

Thanks to Bill Dunlap, Peter Langfelder and Jim Holtman for no less than 3
different
solutions.

JN


On 12-03-01 04:25 PM, Peter Langfelder wrote:
> pstr<-c("b1=200", "b2=50", "b3=0.3")
> split = sapply(strsplit(pstr, split = "="), I);
>
> pnum = as.numeric(split[2, ]);
> names(pnum) = split[1, ];
>