[igraph] Help in power.law.fit

[anupam sinha]

Dear all,
             Apologies for the long mail I am working on directed metabolic networks where enzymes form the nodes of the networks.I am  calculating the beweenness centralities of all the nodes. It is known that the Betweenness centrality values of a network follow a power law distribution. 

>sce_met_bet<-betweenness(sce_met)
> sce_met_bet
  [1] 6.888455e+03 2.683315e+03 2.683315e+03 1.617059e+03 1.617059e+03
  [6] 1.617059e+03 1.617059e+03 5.275100e+01 5.275100e+01 5.275100e+01
 [11] 5.275100e+01 5.275100e+01 5.275100e+01 3.499412e+03 1.311632e+01
 [16] 6.888455e+03 6.888455e+03 9.357711e+01 9.357711e+01 8.515973e+03
 [21] 1.563137e+03 5.132214e+03 4.228698e+03 2.313037e+03 2.313037e+03
 [26] 1.270150e+03 5.023037e+03 5.023037e+03 8.647114e+03 8.647114e+03
 [31] 4.848761e+03 4.848761e+03 5.676499e+03 5.676499e+03 2.244379e+03
 [36] 2.244379e+03 8.450442e+02 8.450442e+02 8.450442e+02 5.615452e+02
 [41] 5.615452e+02 5.615452e+02 5.615452e+02 1.808787e+02 1.006198e+01
 [46] 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01
 [51] 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01
 [56] 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01
 [61] 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01
 [66] 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01 1.006198e+01
 [71] 1.006198e+01 1.006198e+01 1.006198e+01 1.960784e-02 1.960784e-02
 [76] 1.960784e-02 1.960784e-02 1.960784e-02 1.960784e-02 1.960784e-02
 [81] 1.960784e-02 1.960784e-02 1.960784e-02 1.960784e-02 5.626124e+02
 [86] 5.626124e+02 9.559960e+02 9.915876e+02 1.289897e+03 3.267974e-02
 [91] 7.556903e+02 7.556903e+02 1.374163e+03 1.257000e+03 1.939352e+02
 [96] 1.939352e+02 1.939352e+02 1.000000e+00 1.536252e+03 4.570442e+02
[101] 4.570442e+02 2.974417e+02 1.059581e+03 1.059581e+03 3.491835e+00
[106] 3.491835e+00 1.743341e+03 4.253897e+03 4.253897e+03 4.253897e+03
[111] 5.730584e+03 5.730584e+03 5.730584e+03 9.707759e+02 4.453895e+03
[116] 4.453895e+03 5.582883e+03 1.188927e+03 3.021313e-01 3.021313e-01
[121] 3.021313e-01 1.563731e+03 1.535368e+04 2.706545e+03 1.454511e+03
[126] 1.486211e+03 1.486211e+03 1.486211e+03 1.763554e+03 1.797472e+01
[131] 1.797472e+01 1.797472e+01 9.524194e+00 9.524194e+00 4.221586e+02
[136] 4.221586e+02 6.359540e+02 6.359540e+02 1.355708e+01 1.355708e+01
[141] 1.355708e+01 1.355708e+01 1.355708e+01 1.355708e+01 1.355708e+01
[146] 2.874129e+03 5.163042e+01 5.163042e+01 2.133094e+03 2.133094e+03
[151] 1.019328e+04 1.019328e+04 7.582917e+02 7.582917e+02 1.232680e+00
[156] 2.335590e+03 2.165982e+03 1.305459e+04 1.111111e+00 2.165982e+03
[161] 2.165982e+03 2.165982e+03 2.165982e+03 5.901268e+02 8.106954e+02
[166] 8.106954e+02 4.698703e+02 3.908929e+00 3.908929e+00 3.908929e+00
[171] 3.908929e+00 1.642857e+00 7.971633e+02 1.516126e+04 2.152768e+03
[176] 2.152768e+03 4.298223e+03 1.399407e+03 1.399407e+03 3.162380e+02
[181] 3.703704e-01 1.566745e+03 3.703704e-01 3.703704e-01 1.101451e+02
[186] 1.101451e+02 1.044000e+03 5.230000e+02 0.000000e+00 0.000000e+00
[191] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[196] 2.595000e+03 0.000000e+00 0.000000e+00 1.205804e+01 1.712121e+00
[201] 4.666667e+00 4.666667e+00 4.666667e+00 2.288840e+02 2.288840e+02
[206] 2.288840e+02 2.288840e+02 1.205804e+01 1.205804e+01 1.205804e+01
[211] 1.205804e+01 1.205804e+01 1.205804e+01 0.000000e+00 1.044000e+03
[216] 0.000000e+00 4.788143e+03 2.086000e+03 0.000000e+00 0.000000e+00
[221] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 3.000000e+00
[226] 4.000000e+00 3.000000e+00 0.000000e+00 4.400000e+01 3.600000e+01
[231] 2.600000e+01 0.000000e+00 2.400000e+01 2.400000e+01 4.400000e+01
[236] 5.600000e+01 3.600000e+01 2.700000e+01 0.000000e+00 0.000000e+00
[241] 5.400000e+01 5.000000e+01 1.400000e+01 0.000000e+00 0.000000e+00
[246] 2.000000e+00 2.000000e+00 0.000000e+00 0.000000e+00 5.235000e+02
[251] 3.125000e-02 2.480000e+02 2.480000e+02 3.125000e-02 3.125000e-02
[256] 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02
[261] 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02
[266] 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02
[271] 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02
[276] 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02
[281] 3.125000e-02 3.125000e-02 3.125000e-02 3.125000e-02 0.000000e+00
[286] 0.000000e+00 2.080500e+03 2.084000e+03 5.230000e+02 0.000000e+00
[291] 3.195458e+03 1.129769e+03 7.215846e+02 0.000000e+00 0.000000e+00
[296] 4.890952e+03 2.147390e+02 2.233590e+03 6.008137e+03 9.969713e+02
[301] 9.969713e+02 9.969713e+02 9.969713e+02 9.969713e+02 1.726920e+02
[306] 1.726920e+02 0.000000e+00 3.605920e+02 0.000000e+00 5.504479e+02
[311] 2.286936e+03 0.000000e+00 0.000000e+00 6.519338e+02 6.519338e+02
[316] 5.313944e+01 1.843784e+04 6.720126e+02 5.313944e+01 5.313944e+01
[321] 5.313944e+01 2.564620e+03 8.467746e+03 0.000000e+00 0.000000e+00
[326] 1.711131e+03 5.062234e+02 2.888832e+03 7.057377e+01 0.000000e+00
[331] 7.531448e+03 7.531448e+03 1.600699e+04 3.800297e+03 6.447306e+01
[336] 6.447306e+01 6.447306e+01 3.800297e+03 2.432072e+02 4.962506e+02
[341] 1.392406e+03 1.392406e+03 1.521749e+02 1.378169e+02 1.378169e+02
[346] 5.800000e+01 5.800000e+01 1.440672e+02 7.360814e+02 8.584310e+02
[351] 2.121330e+02 5.214112e+02 5.363420e+03 0.000000e+00 1.571821e+03
[356] 5.882353e-02 0.000000e+00 1.967980e+02 0.000000e+00 1.000000e+00
[361] 0.000000e+00 1.066667e+00 0.000000e+00 7.333333e-01 1.213333e+03
[366] 0.000000e+00 5.087236e+02 1.349832e+02 7.246315e+01 7.246315e+01
[371] 1.678137e+01 0.000000e+00 8.542929e+00 2.222837e+01 2.829837e+03
[376] 5.048820e+02 5.048820e+02 5.114642e+01 1.254289e+04 2.857143e-02
[381] 5.230682e+02 1.398101e+04 0.000000e+00 1.339377e+03 4.914689e+02
[386] 1.332537e+03 3.081614e+01 3.081614e+01 1.595385e+04 1.628778e+03
[391] 4.197624e+03 1.906836e+03 1.906836e+03 4.914689e+02 4.914689e+02
[396] 1.250000e-01 1.366911e+00 1.366911e+00 3.113000e+03 3.512720e+02
[401] 3.512720e+02 1.532269e+02 8.897987e+02 1.339384e+01 2.810748e+02
[406] 2.810748e+02 1.339384e+01 4.761905e+00 3.000000e+00 0.000000e+00
[411] 1.046667e+03 0.000000e+00 4.000000e-01 2.181775e+03 2.181775e+03
[416] 7.224483e+03 9.523810e-02 9.523810e-02 8.637310e+03 1.350936e+03
[421] 3.278686e+03 2.865318e+03 1.120598e+02 1.120598e+02 1.473557e+03
[426] 3.560052e+03 2.997936e+03 1.405666e+03 7.481729e+02 2.277576e+03
[431] 6.643229e+03 2.693094e+03 2.857143e-02 2.857143e-02 6.666667e-02
[436] 6.666667e-02 0.000000e+00 5.230000e+02 0.000000e+00 1.257450e+03
[441] 0.000000e+00 0.000000e+00 1.316877e+03 1.563000e+03 6.144000e+03
[446] 1.044000e+03 4.761905e-02 3.698042e+02 3.698042e+02 9.187338e+02
[451] 9.187338e+02 9.187338e+02 3.108000e+03 5.789909e-02 1.345857e+03
[456] 4.772702e+02 9.090909e-02 9.090909e-02 1.345857e+03 2.688696e+02
[461] 4.444205e+02 9.090909e-02 9.090909e-02 5.586235e+02 9.090909e-02
[466] 3.619000e+03 3.108500e+03 4.128100e+03 0.000000e+00 1.045000e+03
[471] 0.000000e+00 1.563500e+03 1.038000e+03 1.038000e+03 2.000000e+00
[476] 4.285714e-01 4.285714e-01 4.285714e-01 1.714286e+00 2.000000e+00
[481] 2.000000e+00 1.666667e-01 1.666667e-01 5.000000e-01 1.966869e+02
[486] 1.444569e+02 2.068806e+03 1.044000e+03 0.000000e+00 5.230000e+02
[491] 4.459482e+03 7.815000e+02 7.815000e+02 0.000000e+00 4.285714e-01
[496] 2.650000e+01 1.050000e+01 4.285714e-01 4.285714e-01 4.285714e-01
[501] 4.285714e-01 4.285714e-01 6.818182e-02 5.000000e-01 2.083500e+03
[506] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[511] 1.563667e+03 1.303000e+03 2.600000e+02 4.635667e+03 1.045000e+03
[516] 0.000000e+00 0.000000e+00 1.666667e+00 2.920166e+03 2.888666e+03
[521] 3.386662e+02 3.386662e+02 3.386662e+02 3.386662e+02 3.386662e+02
[526] 0.000000e+00 0.000000e+00 3.482431e+02 0.000000e+00 0.000000e+00
[531] 0.000000e+00 0.000000e+00 5.000000e+00 0.000000e+00 2.499184e+03
[536] 1.040762e+03 1.037238e+03 6.315396e+02 5.227619e+02 5.192381e+02
[541] 9.669881e+02 9.669881e+02 9.669881e+02 0.000000e+00 0.000000e+00
[546] 0.000000e+00 4.694383e+03 8.333333e-02 5.788889e+01 2.900000e+01
[551] 2.944444e+01 2.944444e+01 2.944444e+01 2.944444e+01 2.944444e+01
[556] 2.944444e+01 2.944444e+01 2.944444e+01 5.011111e+01 4.122222e+01
[561] 4.411111e+01 0.000000e+00 5.933333e+01 4.000000e+00 1.347778e+02
[566] 2.793333e+02 6.116667e+01 0.000000e+00 2.860000e+02 3.000000e+02
[571] 2.700000e+02 3.213333e+02 3.000000e+00 3.683333e+01 6.666667e-01
[576] 6.666667e-01 1.708000e+02 8.000000e-01 1.040000e+02 8.000000e-01
[581] 8.000000e-01 8.000000e-01 7.000000e+01 3.600000e+01 0.000000e+00
[586] 5.800000e+01 0.000000e+00 1.566000e+03 0.000000e+00 0.000000e+00
[591] 2.080000e+03 2.595097e+03 1.000000e+00 0.000000e+00 0.000000e+00
[596] 0.000000e+00 0.000000e+00 5.230000e+02 0.000000e+00 0.000000e+00
[601] 0.000000e+00 0.000000e+00 1.500000e+00 0.000000e+00 0.000000e+00
[606] 0.000000e+00 1.750000e+01 0.000000e+00 1.000000e+00 0.000000e+00
[611] 1.550000e+01 3.000000e+00 3.000000e+00 5.000000e-01 4.625000e+01
[616] 9.641667e+01 2.500000e-01 9.125000e+01 4.750000e+00 3.166667e+00
[621] 4.233333e+01 3.333333e+00 4.233333e+01 3.166667e+00 3.166667e+00
[626] 4.625000e+01 3.166667e+00 3.166667e+00 9.900000e+01 0.000000e+00
[631] 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[636] 0.000000e+00 0.000000e+00 0.000000e+00 1.986111e+00 3.611111e-01
[641] 1.436111e+00 1.436111e+00 1.561111e+00 2.136111e+01 3.700000e+00
[646] 3.700000e+00 2.361111e-01 1.986111e+00 2.361111e-01 0.000000e+00
[651] 0.000000e+00 1.322997e+02 1.322997e+02 0.000000e+00 0.000000e+00
[656] 3.666667e+03 3.666667e+03 3.666667e+03 0.000000e+00 1.000000e+00
[661] 0.000000e+00 0.000000e+00 0.000000e+00 9.000000e+00 4.285714e-01
[666] 3.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[671] 3.000000e+00 1.666667e-01 0.000000e+00 9.055310e+01 0.000000e+00
[676] 1.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
[681] 1.062060e+04 8.220000e+01 2.520000e+01 2.520000e+01 2.520000e+01
[686] 2.520000e+01 2.520000e+01 2.520000e+01 2.520000e+01 2.520000e+01
[691] 2.520000e+01 2.520000e+01 2.520000e+01 2.520000e+01 2.520000e+01
[696] 2.520000e+01 2.520000e+01 2.520000e+01 2.520000e+01 2.520000e+01
[701] 2.520000e+01 5.700000e+01 0.000000e+00 5.230000e+02 2.595000e+03
[706] 3.108000e+03 3.619000e+03 5.140000e+03 5.643000e+03 2.595200e+03
[711] 3.466667e+02

> power.law.fit(sce_met_bet)
Error in optim(start, f, method = method, hessian = TRUE, ...) : 
  initial value in 'vmmin' is not finite



 I have a couple of queries 

1 . Is it appropriate for me to  fit power law distribution to this dataset?

2. Why am I getting this error?