[R] Matrix to data frame conversion

[MacQueen, Don]

So, if you have duplicate row.names, get rid of them. Try

  rownames(comb_model0) <- NULL
  as.data.frame(comb_model0)

-Don

-- 
Don MacQueen

Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062





On 11/12/12 7:45 AM, "PavloEs" <nicippe at gmail.com> wrote:

>I have a matrix which I wanted to convert to a data frame. As I could not
>succeed and resorted to export to csv and reimport it again. Why did I
>fail
>in the attempt and how can I achieve what I wanted without  this
>roundabouts?
> 
>The original matrix:
>
>> str(comb_model0)
> num [1:90, 1:4] 3.5938 0.0274 0.0342 0.0135 0.0207 ...
> - attr(*, "dimnames")=List of 2
>  ..$ : chr [1:90] "(Intercept)" "as.factor(dow)1" "as.factor(dow)2"
>"as.factor(dow)3" ...
>  ..$ : chr [1:4] "Estimate" "Std. Error" "t value" "Pr(>|t|)"
>> dim(comb_model0)
>[1] 90  4
>> class(comb_model0)
>[1] "matrix"
>> 
>> 
>> head(comb_model0,10)
>                                  Estimate Std. Error t value    Pr(>|t|)
>(Intercept)                       3.593793   0.012537 286.656 0.000000000
>as.factor(dow)1                   0.027378   0.007348   3.726 0.000196109
>as.factor(dow)2                   0.034211   0.007348   4.656 0.000003288
>as.factor(dow)3                   0.013481   0.007393   1.823 0.068281371
>as.factor(dow)4                   0.020708   0.007358   2.814 0.004903774
>as.factor(dow)5                   0.030164   0.007327   4.117 0.000038886
>as.factor(dow)6                   0.021723   0.007327   2.965 0.003039448
>as.factor(fluepi)      0.044272   0.014697   3.012 0.002601912
>o3max                             0.003441   0.001723   1.998 0.045785798
>
>One of the many conversion attempts:
>
>> xx<-as.data.frame(comb_model0)
>> xx
>Error in data.frame(Estimate = c(" 3.59379258", " 0.02737812", "
>0.03421067",  : 
>  duplicate row.names: (Intercept), as.factor(dow)1, as.factor(dow)2,
>as.factor(dow)3, as.factor(dow)4, as.factor(dow)5, as.factor(dow)6,
>as.factor(fluepi)
>
>
>write.csv(comb_model0, "test.csv")
>
>test<-read.csv("test.csv")
>class(test)
>[1] "data.frame"
>
>> dim(test)
>[1] 90  5
>
>head(test,9)
>                                   X    Estimate Std..Error   t.value
>Pr...t..
>1                        (Intercept)  3.59379258   0.012537 286.65611
>0.000000000
>2                    as.factor(dow)1  0.02737812   0.007348   3.72596
>0.000196109
>3                    as.factor(dow)2  0.03421067   0.007348   4.65575
>0.000003288
>4                    as.factor(dow)3  0.01348142   0.007393   1.82343
>0.068281371
>5                    as.factor(dow)4  0.02070761   0.007358   2.81419
>0.004903774
>6                    as.factor(dow)5  0.03016411   0.007327   4.11665
>0.000038886
>7                    as.factor(dow)6  0.02172334   0.007327   2.96476
>0.003039448
>8  	  as.factor(fluepi)  0.04427231   0.014697   3.01232 0.002601912
>9                           o3max     0.00344111   0.001723   1.99772
>0.045785798
>
>
>
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>ml
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