[R] Converting dataframe to matrix
Noah Silverman
noah at smartmediacorp.com
Fri Oct 16 10:55:03 CEST 2009
I think you may be correct.
I've manage to get the data into a format that the function accepts.
The error appears to be because I have negative values in my data:
Error in apply(safeNormCDF(s), 1, prod) :
dim(X) must have a positive length
On 10/16/09 1:51 AM, Philipp Pagel wrote:
> On Fri, Oct 16, 2009 at 01:33:14AM -0700, Noah Silverman wrote:
>
>> Hi,
>>
>> I'm experimenting with a few learners that require a matrix as their
>> input. (Currently svmpath, vbmp, etc.)
>>
>> I currently have a dataframe with 50 columns and 20,000 rows.
>>
>> I tried using:
>>
>> x<- as.matrix(my_data.frame)
>>
>> If I then as, "is.matrix(x)", I get TRUE.
>>
>> However everywhere I've tried to use the matrix returns errors.
>>
> Without more information I can't even start to guess what is going
> wrong. Please give a short, reproducible example of what you did and
> what errors you encountered.
>
> as.matrix() should suffice for creating a matrix from a data.frame :
>
>
>> foo<- data.frame(1:4, 4:1, sqrt(1:4), log(4:1))
>> foo
>>
> X1.4 X4.1 sqrt.1.4. log.4.1.
> 1 1 4 1.000000 1.3862944
> 2 2 3 1.414214 1.0986123
> 3 3 2 1.732051 0.6931472
> 4 4 1 2.000000 0.0000000
>
>> det(foo)
>>
> Error in UseMethod("determinant") :
> no applicable method for "determinant"
>
>> det(as.matrix(foo))
>>
> [1] -0.1092489
>
> So probably your problem is somewhere else.
>
> cu
> Philipp
>
>
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