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## Re: [igraph] find highest degrees

**From**: |
John Lapeyre |

**Subject**: |
Re: [igraph] find highest degrees |

**Date**: |
Sat, 20 Feb 2010 20:23:25 +0100 |

**User-agent**: |
KMail/1.12.4 (Linux/2.6.31.9; KDE/4.3.4; x86_64; ; ) |

>* VECTOR(v) gives you the underlying C array of a VECTOR.*
Yes I forgot that.
>* There is a function called igraph_vector_copy_to(), that does almost*
>* the same, the only difference is that it copies the whole vector.*
That one is perfect. I missed it.
>* Btw. I think it is simpler to sort the two vectors and then merge*
>* them. This involves copying them, of course, but the heap approach*
>* copies as well, and I guess that the C library quicksort will be*
>* faster than the heap-sort. Even if it is not faster, it is surely*
>* easier to implement, you just need to*
>* *
>* 1. copy the two vectors*
>* 2. sort them*
>* 3. merge them (this needs a vector_union_sorted function), but this is*
>* trivial to write.*
You are talking about the union, I think ? I haven't
needed it yet. But I'll probably use your approach when I do
need it. So far, I only needed the cardinality of the
union. For that, I did no copying, sorting of one vector and binary
searching in the sorted vector.