to do subtractFrom, you can instead just do Vector.assign(otherVector, Functions.minus);
The problem is that while DenseVector has an optimization here: if the BinaryFunction passed in is additive (it's an instance of PlusMult), sparse iteration over "otherVector" is executed, applying the binary function and mutating self. AbstractVector should have this optimization in general, as it would be useful in RandomAccessSparseVector (although not terribly useful in SequentialAccessSparseVector, but still better than current). -jake On Thu, Feb 18, 2010 at 1:19 PM, Robin Anil <robin.a...@gmail.com> wrote: > I just had to change it at one place(and the tests pass, which is scary). > Canopy is really fast now :). Still could be pushed > Now the bottleneck is minus > > maybe a subtractFrom on the lines of addTo? or a mutable negate function > for > vector, before adding to > > Robin > > > > On Fri, Feb 19, 2010 at 2:43 AM, Jake Mannix <jake.man...@gmail.com> > wrote: > > > I use it (addTo) in decomposer, for exactly this performance issue. > > Changing > > plus into addTo requires care, because since plus() leaves arguments > > immutable, > > there may be code which *assumes* that this is the case, and doing > addTo() > > leaves side effects which might not be expected. This bit me hard on svd > > migration, because I had other assumptions about mutability in there. > > > > -jake > > > > On Thu, Feb 18, 2010 at 1:09 PM, Robin Anil <robin.a...@gmail.com> > wrote: > > > > > ah! Its not being used anywhere :). Should we make that a big task > before > > > 0.3 ? Sweep through code(mainly clustering) and change all these > things. > > > > > > Robin > > > > > > > > > > > > On Fri, Feb 19, 2010 at 2:36 AM, Sean Owen <sro...@gmail.com> wrote: > > > > > > > Isn't this basically what assign() is for? > > > > > > > > On Thu, Feb 18, 2010 at 9:04 PM, Robin Anil <robin.a...@gmail.com> > > > wrote: > > > > > Now the big perf bottle neck is immutability > > > > > > > > > > Say for plus its doing vector.clone() before doing anything else. > > > > > There should be both immutable and mutable plus functions > > > > > > > > > > > > > > >
