[R] Creating a Hash from Data.Frame

jim holtman jholtman at gmail.com
Mon Jun 16 04:03:19 CEST 2008


here is a way:

> x <- read.table(textConnection("#GDS_ID GENE_NAME GENE_DESCRIPTION GENE_FUNCTION
+ 1007_s_at | DDR1 | discoidin domain receptor tyrosine kinase 1 |
protein-coding
+ 1053_at | RFC2 | replication factor C (activator 1) 2, 40kDa | protein-coding
+ 117_at | HSPA6 | heat shock 70kDa protein 6 (HSP70B') |
protein-coding"), sep="|",
+ strip.white=TRUE, quote='')   # you need strip.white on the call
> closeAllConnections()
> str(x)
'data.frame':   3 obs. of  4 variables:
 $ V1: Factor w/ 3 levels "1007_s_at","1053_at",..: 1 2 3
 $ V2: Factor w/ 3 levels "DDR1","HSPA6",..: 1 3 2
 $ V3: Factor w/ 3 levels "discoidin domain receptor tyrosine kinase
1",..: 1 3 2
 $ V4: Factor w/ 1 level "protein-coding": 1 1 1
> x
         V1    V2                                          V3             V4
1 1007_s_at  DDR1 discoidin domain receptor tyrosine kinase 1 protein-coding
2   1053_at  RFC2 replication factor C (activator 1) 2, 40kDa protein-coding
3    117_at HSPA6        heat shock 70kDa protein 6 (HSP70B') protein-coding
> mydata <- character()
> mydata[as.character(x$V2)] <- as.character(x$V3)
> mydata["RFC2"]  #access the data
                                         RFC2
"replication factor C (activator 1) 2, 40kDa"
>

remember to add the 'strip.white=TRUE' on read.table

On Sun, Jun 15, 2008 at 9:53 PM, Gundala Viswanath <gundalav at gmail.com> wrote:
> Hi,
>
> I have the following data frame:
>
>> print(mydatframe)
>
> __DATAFRAME__
>
>   V1    V2 V3
> 1 1007_s_at  DDR1  discoidin domain receptor tyrosine kinase 1
> 2 1053_at  RFC2  replication factor C (activator 1) 2, 40kDa
> 3 117_at  HSPA6  heat shock 70kDa protein 6 (HSP70B')
>
> __END__
>
> Is there a way to create a hash with
> V2 as Key and V3 as its value?
>
> - Gundala Viswanath
> Jakarta - Indonesia
>
> ______________________________________________
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> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>



-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem you are trying to solve?



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