Re: Matrix multiplication in spark

2014-11-05 Thread ll
@sowen.. i am looking for distributed operations, especially very large sparse matrix x sparse matrix multiplication. what is the best way to implement this in spark? -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/Matrix-multiplication-in-spark

Re: Matrix multiplication in spark

2014-11-05 Thread Xiangrui Meng
am looking for distributed operations, especially very large sparse matrix x sparse matrix multiplication. what is the best way to implement this in spark? -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/Matrix-multiplication-in-spark-tp12562p18164.html

Re: Matrix multiplication in spark

2014-11-05 Thread Duy Huynh
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Re: Matrix multiplication in spark

2014-11-05 Thread Shivaram Venkataraman
is the best way to implement this in spark? -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/Matrix-multiplication-in-spark-tp12562p18164.html Sent from the Apache Spark User List mailing list archive at Nabble.com

Matrix multiplication in spark

2014-08-21 Thread phoenix bai
there is RowMatrix implemented in spark. and I check for a while but failed to find any matrix operations (like multiplication etc) are defined in the class yet. so, my question is, if I want to do matrix multiplication, (to do vector x matrix multiplication to be precise), need to convert the

Re: Matrix multiplication in spark

2014-08-21 Thread Sean Owen
Are you trying to multiply dense or sparse matrices? if sparse, are they very large -- meaning, are you looking for distributed operations? On Thu, Aug 21, 2014 at 10:07 AM, phoenix bai mingzhi...@gmail.com wrote: there is RowMatrix implemented in spark. and I check for a while but failed to

Re: Matrix multiplication in spark

2014-08-21 Thread x
You could create a distributed matrix with RowMatrix. val rmat = new RowMatrix(rows) And then make a local DenseMatrix. val localMat = Matrices.dense(m, n, mat) Then multiply them. rmat.multiply(localMat) xj @ Tokyo On Thu, Aug 21, 2014 at 6:37 PM, Sean Owen so...@cloudera.com wrote: Are

Re: Matrix multiplication in spark

2014-08-21 Thread x
Yes. Now Spark API doesn't provide transpose function. You have to define it like below. def transpose(m: Array[Array[Double]]): Array[Array[Double]] = { (for { c - m(0).indices } yield m.map(_(c)) ).toArray } xj @ Tokyo On Thu, Aug 21, 2014 at 10:12 PM, phoenix bai