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I am trying to use the sparse vector class in the JScience package but I am confused as to how. I want to make several sparse vectors of dimension, say, 1000. But, I see that there is no constructor and also suppose that I want to put certain values in a sparse vector at certain indexes, how is this supposed to be achieved?

Lucas Alanis
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From the documentation:

Sparse vectors can be created using an index-to-element mapping or by adding single elements sparse vectors together.

This corresponds to the first two static valueOf methods.

Single Element

valueOf(int dimension, F zero, int i, F element)

Returns a sparse vector having a single element at the specified index.

Using a Mapping

valueOf(int dimension, F zero, java.util.Map<javolution.util.Index,F> elements)

Returns a sparse vector from the specified index to element mapping.

Alexis King
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  • So I could use a HashMap for example to make a sparse vector? And should I set `zero` to 0 if I want a sparse vector with zeros being the most abundant value? – Lucas Alanis Jan 25 '15 at 23:55
  • @LucasAlanis Yes, you could use a HashMap. For the `zero` argument, you would provide the element of the particular field that represents zero. For example, if you were using a [Real](http://jscience.org/api/org/jscience/mathematics/number/Real.html) field, you would pass `Real.ZERO`. – Alexis King Jan 25 '15 at 23:59