manipulating a character "with.several.periods..01"

[chuck.01]

Hi,

how do I make this character:

"Lab.01.Entrance..1999102."

look like this

"Lab 01 Entrance (1999102)"

??

I thought about strsplit() and then a bunch of paste statements, but there has to be an easier way.
Thanks for any ideas.
-Chuck

[arun kirshna]

HI,
Try this:
new1<-"Lab.01.Entrance..1999102."
new2<-gsub("\\."," ",new1)
 gsub("(.*\\s.*\\s.*)\\s+(.*)\\s","\\1(\\2)",new2)
#[1] "Lab 01 Entrance (1999102)"
#or
gsub("(.*Entrance{0,1})\\s+(.*)\\s","\\1 (\\2)",new2)
#[1] "Lab 01 Entrance (1999102)"
A.K.

[arun kirshna]

Hi,

Another one step approach:
new1<-"Lab.01.Entrance..1999102."
gsub("(.*)\\.(.*)\\.(.*)\\.\\.(.*)\\.","\\1 \\2 \\3 (\\4)",new1)
#[1] "Lab 01 Entrance (1999102)"
A.K.

[chuck.01]

Thank you greatly Arun.

Could you please tell me what this is generally called:

\.(.*)\\.(.*)\\.\\.

it makes no sense, and I would like to find some documentation so I can understand it.
Thanks so much!

arun kirshna wrote

Hi,

Another one step approach:
new1<-"Lab.01.Entrance..1999102."
gsub("(.*)\\.(.*)\\.(.*)\\.\\.(.*)\\.","\\1 \\2 \\3 (\\4)",new1)
#[1] "Lab 01 Entrance (1999102)"
A.K.

[chuck.01]

are these "regular expressions" used in the grep() and gsub() functions?

chuck.01 wrote

Thank you greatly Arun.

Could you please tell me what this is generally called:

\.(.*)\\.(.*)\\.\\.

it makes no sense, and I would like to find some documentation so I can understand it.
Thanks so much!

arun kirshna wrote

Hi,

Another one step approach:
new1<-"Lab.01.Entrance..1999102."
gsub("(.*)\\.(.*)\\.(.*)\\.\\.(.*)\\.","\\1 \\2 \\3 (\\4)",new1)
#[1] "Lab 01 Entrance (1999102)"
A.K.

[arun kirshna]

HI,

Yes, these are regular expressions.

#To understand it, may be it is easier to split the whole gsub()
#Here, the expression inside the first quotes look for the pattern to match; the expression inside the second quote is #the replacement.
#For example, if I want to return only "Lab" or "01" or "Entrance"
gsub("(.*)\\.(.*)\\.(.*)\\.\\.(.*)\\.","\\1",new1)
#[1] "Lab"
 gsub("(.*)\\.(.*)\\.(.*)\\.\\.(.*)\\.","\\2",new1)
#[1] "01"
 gsub("(.*)\\.(.*)\\.(.*)\\.\\.(.*)\\.","\\3",new1)
#[1] "Entrance"
This can be also achieved with a simple expression
 gsub("(Lab{0,1}).*","\\1",new1)
#[1] "Lab"
#In the whole expression
gsub("(.*)\\.(.*)\\.(.*)\\.\\.(.*)\\.","\\1 \\2 \\3 (\\4)",new1)
new1<-"Lab.01.Entrance..1999102."
"\\1" (first parenthesis from left) will return "Lab", escaped "." with "\\."
".*" means zero or more of any character.
If you follow the logic, dots are replaced with spaces inside the second " ".

Hope it helps.
A.K.

[arun kirshna]

Hi,

If I change the string a little bit, and if I want to get the same result or slightly different results:
new2<- "Lab.01_Entrance._1946."
 gsub("(.*)\\.(.*)\\_(.*)\\.\\_(.*)\\.","\\1 \\2 \\3 (\\4)",new2)
#[1] "Lab 01 Entrance (1946)"
gsub("(.*)\\.(.*)\\_(.*)\\.\\_(.*)\\.","\\1 (\\2) \\3 (\\4)",new2)
#[1] "Lab (01) Entrance (1946)"
A.K.

[chuck.01]

You are awesome; Thanks for this great starting point.  I will take it from here.  
Cheers!

arun kirshna wrote

Hi,

If I change the string a little bit, and if I want to get the same result or slightly different results:
new2<- "Lab.01_Entrance._1946."
 gsub("(.*)\\.(.*)\\_(.*)\\.\\_(.*)\\.","\\1 \\2 \\3 (\\4)",new2)
#[1] "Lab 01 Entrance (1946)"
gsub("(.*)\\.(.*)\\_(.*)\\.\\_(.*)\\.","\\1 (\\2) \\3 (\\4)",new2)
#[1] "Lab (01) Entrance (1946)"
A.K.