[R] dropping rows

[Tobias Muhlhofer]

Thanks.

The problem is that there is extremely little on dataframes or matrices 
in "An Intro to R", which I did read and I frankly don't know where else 
to go.

Once I know a function like subset() exists, I can then read the help 
files on it and that's fine, but I would never dream this function up 
myself...

As for indexing, I DID read "An Introduction to R" and I did NOT catch 
the part where it says you can use any variable in the dataframe to 
index it, nor would I have thought of it by myself. From that 
documentation, I only learned about using row-labels to index things...

But I am definitely thankful for the quick help given to me by people on 
this list, and so I guess being RTFM'ed is a small price to pay for 
figuring out how to solve the problem I need to solve.

Toby


Jeff Laake wrote:
> Here's an example:
> 
> earlydata=data[data$year<1960,]
> 
> Lookup help and read manuals on manipulating dataframes.
> 
> 
> Tobias Muhlhofer wrote:
> 
>> Hi!
>>
>> Sorry for asking a trivial questions, but I can't seem to figure this 
>> out.
>>
>> I have a dataframe called master containing 30-odd variables.
>>
>> In this dataframe, I have observations across these 30 variables from 
>> 1930 to 2003 (I've made a "year" variable). How can I drop all rows 
>> for which the year is less than 1960? I'm assuming something with 
>> ifelse() but I can't quite figure it out.
>>
>> I would appreciate a suggestion of some syntax.
>>
>> Thanks!
>>     Toby
>>
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> 
> 
> 
> 
> 

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