Converting an XTS object to a data.frame [duplicate]

Question

Possible Duplicate:
How to create a variable of rownames?

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Please run it in R:

require(quantmod)   
setSymbolLookup(SDB=list(name="000001.sz",src="yahoo"))   
getSymbols("SDB",from="2010-01-01",to="2010-02-01")   
sdb=as.data.frame(weeklyReturn(SDB))  
sdb    

What I get is:

           weekly.returns             
2010-01-08    -0.07830343          
2010-01-15    -0.05176991              
2010-01-22     0.07699487              
2010-01-29    -0.05979203         
2010-02-01    -0.02119816 

What I want to get is:

        date  weekly.returns                   
1 2010-01-08     -0.07830343           
2 2010-01-15     -0.05176991         
3 2010-01-22      0.07699487          
4 2010-01-29     -0.05979203            
5 2010-02-01     -0.02119816 

How can I do this?

Note that this is an XTS object, not a basic data.frame. After the conversion, I want the original rownames to appear as a new variable in the resulting data.frame.

Answer 1

Ok. So, it's not exactly the same as your earlier question since this is an XTS object. Still, very easy to take care of:

data.frame(date = index(weeklyReturn(SDB)), 
           weeklyReturn(SDB), row.names=NULL)
#         date weekly.returns
# 1 2010-01-04    -0.03303426
# 2 2010-01-11    -0.04681569
# 3 2010-01-18    -0.05000000
# 4 2010-01-25     0.03353517
# 5 2010-02-01    -0.04281208

For help on what is being done here, view use ?indexClass to read the documentation for index in the XTS package.