Re: [R] How to take out the content of character string

2010-03-15 Thread jq81

Thank you all so much for the help!
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Re: [R] How to take out the content of character string

2010-03-11 Thread Thomas Lumley

On Wed, 10 Mar 2010, Henrique Dallazuanna wrote:


On Wed, Mar 10, 2010 at 7:50 PM, Thomas Lumley tlum...@u.washington.edu wrote:

On Wed, 10 Mar 2010, baptiste auguie wrote:


Hi,

it's generally considered a bad practice but try this,

eval(parse(text=AA))

library(fortunes)
fortune(106)

HTH,

baptiste

On 10 March 2010 07:46, jq81 jingqia...@gmail.com wrote:


My question is represented by the following example.

For example, I have a character string a, which is defined as

AA=list(x=1, y=2)

I want to take out the content of AA by using some function, so that I
can
obtain the following expression automatically.

list(x=1, y=2)



This is the situation where it isn't considered bad practice.  If someone
hands you a string with code in it, the only way to parse it is with
parse().


I think that Is there another way:

source(textConnection(AA))$value
closeAllConnections()



And if you look at the code for source(), you will see that it uses parse() and 
eval().

-thomas

Thomas Lumley   Assoc. Professor, Biostatistics
tlum...@u.washington.eduUniversity of Washington, Seattle
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Re: [R] How to take out the content of character string

2010-03-10 Thread baptiste auguie
Hi,

it's generally considered a bad practice but try this,

eval(parse(text=AA))

library(fortunes)
fortune(106)

HTH,

baptiste

On 10 March 2010 07:46, jq81 jingqia...@gmail.com wrote:

 My question is represented by the following example.

 For example, I have a character string a, which is defined as

 AA=list(x=1, y=2)

 I want to take out the content of AA by using some function, so that I can
 obtain the following expression automatically.

 list(x=1, y=2)

 Does anyone know how to do it? Thanks a lot,








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 View this message in context: 
 http://n4.nabble.com/How-to-take-out-the-content-of-character-string-tp1587004p1587004.html
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-- 


Baptiste Auguié

Departamento de Química Física,
Universidade de Vigo,
Campus Universitario, 36310, Vigo, Spain

tel: +34 9868 18617
http://webs.uvigo.es/coloides

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and provide commented, minimal, self-contained, reproducible code.


Re: [R] How to take out the content of character string

2010-03-10 Thread Thomas Lumley

On Wed, 10 Mar 2010, baptiste auguie wrote:


Hi,

it's generally considered a bad practice but try this,

eval(parse(text=AA))

library(fortunes)
fortune(106)

HTH,

baptiste

On 10 March 2010 07:46, jq81 jingqia...@gmail.com wrote:


My question is represented by the following example.

For example, I have a character string a, which is defined as

AA=list(x=1, y=2)

I want to take out the content of AA by using some function, so that I can
obtain the following expression automatically.

list(x=1, y=2)



This is the situation where it isn't considered bad practice.  If someone hands 
you a string with code in it, the only way to parse it is with parse().

The problem with eval(parse()) is when people use it to do macro processing or 
other things that are much better done with expressions.

-thomas

Thomas Lumley   Assoc. Professor, Biostatistics
tlum...@u.washington.eduUniversity of Washington, Seattle

__
R-help@r-project.org mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.


Re: [R] How to take out the content of character string

2010-03-10 Thread Henrique Dallazuanna
On Wed, Mar 10, 2010 at 7:50 PM, Thomas Lumley tlum...@u.washington.edu wrote:
 On Wed, 10 Mar 2010, baptiste auguie wrote:

 Hi,

 it's generally considered a bad practice but try this,

 eval(parse(text=AA))

 library(fortunes)
 fortune(106)

 HTH,

 baptiste

 On 10 March 2010 07:46, jq81 jingqia...@gmail.com wrote:

 My question is represented by the following example.

 For example, I have a character string a, which is defined as

 AA=list(x=1, y=2)

 I want to take out the content of AA by using some function, so that I
 can
 obtain the following expression automatically.

 list(x=1, y=2)


 This is the situation where it isn't considered bad practice.  If someone
 hands you a string with code in it, the only way to parse it is with
 parse().

I think that Is there another way:

source(textConnection(AA))$value
closeAllConnections()

 The problem with eval(parse()) is when people use it to do macro processing
 or other things that are much better done with expressions.

    -thomas

 Thomas Lumley                   Assoc. Professor, Biostatistics
 tlum...@u.washington.edu        University of Washington, Seattle

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 PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
 and provide commented, minimal, self-contained, reproducible code.




-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40 S 49° 16' 22 O

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[R] How to take out the content of character string

2010-03-09 Thread jq81

My question is represented by the following example.

For example, I have a character string a, which is defined as

AA=list(x=1, y=2)

I want to take out the content of AA by using some function, so that I can
obtain the following expression automatically.

list(x=1, y=2)

Does anyone know how to do it? Thanks a lot,








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View this message in context: 
http://n4.nabble.com/How-to-take-out-the-content-of-character-string-tp1587004p1587004.html
Sent from the R help mailing list archive at Nabble.com.

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and provide commented, minimal, self-contained, reproducible code.