How to get the string '\'?

I can not get the string '\'. Could somebody let me know how to get  
it?

print('\')

+
+

print('\\')

[1] "\\"

?cat

cat("\\")

\


On Nov 15, 2009, at 5:30 PM, Peng Yu wrote:

I can not get the string '\'. Could somebody let me know how to get it?

print('\')

+
+

print('\\')

[1] "\\"

David Winsemius, MD
Heritage Laboratories
West Hartford, CT

My question was from replacing a pattern by '\\'. How to replace '/'
in string by '\'?

string='abc/efg'
gsub('/','\\',string)

My question was from replacing a pattern by '\\'. How to replace '/'
in string by '\'?

string='abc/efg'
gsub('/','\\',string)

On Nov 15, 2009, at 6:35 PM, Peng Yu wrote:

My question was from replacing a pattern by '\\'. How to replace '/'
in string by '\'?

string='abc/efg'
gsub('/','\\',string)

No, ?that was most definitely _not_ your posed question. If you want now to
change your question and supply a reproducible example, that's fine, just
don't claim that your mind should have been read more properly that it was,
.... please.

The problem with your _second_ question is that the printed representation
of "\" is a problem because of its special use as an escape symbol. So
sometimes it needs to be displayed as "\\". What gets written to the screen
may be different that the internal representation. Look at the results of:

string='abc/efg'
cat(gsub('/','\\\\',string), file="test.txt")

You should see:
abc\efg

...although at the screen you would see:

string='abc/efg'
gsub('/','\\\\',string)

[1] "abc\\efg"

The first "\" escapes second "\" which in turn allows whatever follows to be
interpreted as "escaped", while the third "\" escapes the 4th "\" so that it
can be examined by the R interpreter as a real "\".


--
David.

On Sun, Nov 15, 2009 at 5:07 PM, David Winsemius <dwinsemius at comcast.net>
wrote:

?cat

cat("\\")

\


On Nov 15, 2009, at 5:30 PM, Peng Yu wrote:

I can not get the string '\'. Could somebody let me know how to get it?

print('\')

+
+

print('\\')

[1] "\\"

David Winsemius, MD
Heritage Laboratories
West Hartford, CT

David Winsemius, MD
Heritage Laboratories
West Hartford, CT