Sparse Arrays question
- To: mathgroup at smc.vnet.net
- Subject: [mg73244] Sparse Arrays question
- From: "Christoph Lhotka" <lhotka at astro.univie.ac.at>
- Date: Thu, 8 Feb 2007 03:46:03 -0500 (EST)
Hello!
It is very comfortable, that for a given sparse array it is easy to update or
modify elements using the fact, that prepending new array rules to the old
array rules just overwrite the old definitions. My question: Is this true in
general or just luck, which may be modified in future versions of Mathematica?
Has anybody found a description of this issue in the documentation?
best regards Christoph
PS: In p=SparseArray[{1->2.,2->3.},{10}],
SparseArray[Join[{1->3.,3->4.},ArrayRules[p]],{10}] gives
SparseArray[{1->3.,2->3.,3->4.},{10}]