And, do you really need an inverse, or pseudo-inverse?
But, no, there are really no direct utilities for this. But we could
probably tell you how to do it efficiently, as long as you don't
actually mean a full inverse.

On Fri, Jan 18, 2013 at 11:58 AM, Ted Dunning <[email protected]> wrote:
> Left unsaid in this comment is the fact that matrix inversion of any
> sizable matrix is almost always a mistake because it is (a) inaccurate, (b)
> slow.
>
> In scalable numerics it is also commonly true that the only really scalable
> problems are sparse.  The reason for that is that systems whose cost grows
> with O(n^2) cannot be scaled to arbitrary size n.  Sparse systems with only
> k items on average per row can often be handled with o(n) complexity which
> a requirement for a practical system.
>
> On Thu, Jan 17, 2013 at 8:49 PM, Koobas <[email protected]> wrote:
>
>> Martix inversion, as in explicitly computing the inverse,
>> e.g. computing variance / covariance,
>> or matrix inversion, as in solving a linear system of equations?
>>
>>
>> On Thu, Jan 17, 2013 at 7:49 PM, Colin Wang <
>> [email protected]
>> > wrote:
>>
>> > Hi All,
>> >
>> > I want to solve the matrix inversion, of course, big size, in Map/Reduce
>> > way.
>> > I don't know if Mahout offers this kind of utility. Could you please give
>> > me some tips?
>> >
>> > Thank you,
>> > Colin
>> >
>>

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