R- Convert data into matrix format same as other matrix

Question

I have data in excel as:

     Terms       Category  Weight

      email       TV          1.00

      acccount    Email       12.0

      accept      Phone       3.00

I have other matrix and its format is:

   Terms   TV    Email  Phone  Contact    Information  Support .....

   achieve  1    0.       0      0         0             0
   acquired 0    10.20    0      0         0             0
   across   0    0        3.00   0          0            0

now I want to convert above data into above format like

   Terms   TV    Email  Phone  Contact    Information  Support .....

    email    1    0.       0      0         0.0          0
    acccount 0    12.0    0      0         0.0          0
    accept   0    0        0      1.23       0          0

I want to do this by program in R. Any help will be appreciated. Thanks in advance.

can't you provide some data? It would be useful reading [this SO topic](http://stackoverflow.com/q/5963269/640783) — Paulo E. Cardoso, Apr 22 '14 at 13:42
@Paulo Cardoso You can't merge by "Terms" and get the result OP wants — infominer, Apr 22 '14 at 14:01

score 3 · Accepted Answer · answered Apr 22 '14 at 14:04

3

You need to reshape your data. Install the package "reshape2" if you don't already have it

Here's the code to reshape your data

require(reshape2)
df.reshape <-melt(df, id.var=c("Terms", "Category")) 
#where df is your data.frame to be reshaped
#using both terms and category as ID variables
#now reshape it to wide format by casting
df.wide <-dcast(df.reshape, Terms~Category)

Note this will give you NA's for pairs that don't exist in your data. Which you can easily replace with zeros if you want

And here's a nice tutorial for using reshape2 http://www.seananderson.ca/2013/10/19/reshape.html

answered Apr 22 '14 at 14:04

infominer

1,981
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17

Erase one comma in `dcast` – David Arenburg Apr 22 '14 at 14:06
(+1) nice use of `melt` and `dcast` – David Arenburg Apr 22 '14 at 14:10
Thank you guys.. got what I want. thank you very much :) – indra_patil Apr 23 '14 at 08:56

R- Convert data into matrix format same as other matrix

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