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pajek:faq:varga [2015/07/29 03:52] (current)
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+====== Varga's transformation ======
+
+
+  Subject:        Re: [SOCNET] need for a procedure
+  From:           "varga attila" <tdskusz@yahoo.com>
+  Date:           Fri, August 28, 2009 09:54
+
+  I hope this expression will be understendable!
+    node "i" and "j" have values "m" and "n", edge "ij" has value "k"
+  I wan't to compute these quantities.
+  These have to be valued lines i.e. valued arcs:
+    k/m=ij
+    k/n=ji
+
+  Varga Attila
+
+Thanks to Andrej who added to Pajek operations
+  Net/Transform/Remove/Triangle
+it is now possible to make this transformation in Pajek.
+
+<html>
+<pre>
+output   operation
+Ndir   : Net/Transform/Edges -> Arcs [Yes]
+U      : Net/Transform/Remove/Triangle/Lower [Yes]
+       : select Ndir
+L      : Net/Transform/Remove/Triangle/Upper [No]
+q=1/p  : Vector/Transform/Invert
+       : select U
+q#U    : Operations/Vector/Vector#Network/Output
+       : select L
+q#L    : Operations/Vector/Vector#Network/Input
+       : select q#U as second network
+U+L    : Nets/Union of lines
+       : Net/Transform/Remove/Multiple Lines/Min Value [No]
+       : dispose auxiliary data
+</pre>
+</html>
+This sequence of commands is stored also in the macro **''Varga.mcr''**
+and you can make the transformation simply by selecting the
+network and vector and then running the macro {{:dl:varga.zip}}
+  Macro/Play  [Varga.mcr]
+
+
+**input :** Valued network w[i,j], vector p[i] with nonzero values\\
+**output:** Directed network v[i,j] with values v[i,j] = w[i,j]/p[i], i<j  and  v[i,j] = w[i,j]/p[j], j<i \\
+
+For example, for the input data (vargaTest.net and vargaTest.vec)
+<html>
+<pre>
+        w     1  2  3  4      p
+------------------------     ---
+ v1     1.    6  0  5 10      2
+ v2     2.    0  0  1  4      3
+ v3     3.    5  1  3  8      1
+ v4     4.   10  4  8  0      4
+
+we get
+        v       1    2    3    4
+--------------------------------
+ v1     1.   3.00 0.00 2.50 5.00
+ v2     2.   0.00 0.00 0.33 1.33
+ v3     3.   2.50 0.33 3.00 8.00
+ v4     4.   5.00 1.33 8.00 0.00
+</pre>
+</html>
+The macro **''varga''** was prepared by Vladimir Batagelj on 6. September 2009.
+