PCA降维
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PCA简化数据
- PCA简化数据
- 引言
- 基本概念
- 过程原理
- 重要的概率论和线性代数
- 代码详解
- 总结
- 数据最下方没东西了
引言
不多说了,PCA就是用来降维操作的,将多维数据处理成维数比较少的数据,保留重要特征。
基本概念
PCA是主要成分分析(Principal component analysis, PCA)。 在PAC中数据从原来的坐标系转化到新的坐标系中,新的坐标系的选择是又数据本身决定的。第一个坐标轴的选取是原始数据中方差最大的方向,第二个坐标和第一个坐标正交且方差最大的方向,该过程是重复的。
过程原理
首先我们得到数据,第一个坐标轴的选取是原始数据中方差最大的方向,很明显是直线B,第二个坐标和第一个坐标正交且方差最大的方向,比较明显直线C符合要求,
再拿个例子,将下图二维降维到一维。
前面我们提到第一个主要的成分是数据中差异最大的方向选出来的,第二的成分则是数据差异性次大的方向,并且与第一个方向正交,通过数据的协方差的特征值和特征矩阵分析就可以得到这些数据。得到前N个重要的方向,然后在数据转到这前N个方向做的坐标上
伪代码:
去除均值 计算协方差矩阵 计算协方差矩阵的特征值和特征向量 将特征值降序 保留前N个特征向量 将数据转到N二哥特征向量建的新的空间中
重要的概率论和线性代数
首先来说一下协方差矩阵这个知识吧,对于方差这个知识应该比较熟悉吧,方差矩阵也不是什么难点。对于协方差了来说,百度给出的定义是协方差分析是建立在方差分析和回归分析基础之上的一种统计分析方法。 方差分析是从质量因子的角度探讨因素不同水平对实验指标影响的差异。
期望值分别为E[X]与E[Y]的两个实随机变量X与Y之间的协方差Cov(X,Y)定义为:
Cov(X,Y) = E[(X-E[X])(Y-E[Y])]
从直观上来看,协方差表示的是两个变量总体误差的期望。
说这些还是比较难理解协方差矩阵的意义,简洁的说吧,一个nxm的矩阵X,X的列协方差矩阵的是一个mxm的矩阵,对角线Kij(i = j)是这一列的方差。其他位置是对应的Kij是i列和j列的相关性,Kij为0时没有相关性。要得到方差最大又要得到最小相关度,那么最简单的就是对矩阵协方差做对角化,然后排序,最大的就是方差最大和相关度最小的。
其次重要的是线代中矩阵乘法的几何意义,这里我只给出结论:矩阵X和Y的乘法是将X在Y上的映射,即X以Y为基的映射,也可以是说X在Y上的投影。如果Y的维度要小,就达到了降维的目的。假如Z=X*Y那么,Z就是X在Y上的投影,也可以说Z是X经过Y变换来的。Z乘Y.T就把Z给变回来
再次重要的是线代中矩阵的特征值和特征向量,《线性代数》课本中是这么定义的:设A是n阶方阵,如果存在数λ和n维非零列向量x,使的成立,则称数λ是方阵A的特征值,非零向量x成为A的对应特征值λ的特征向量,λ值的大小表示A在x方向上的拉伸程度,我们通过特征值分解得到的前N个特征向量,那么就对应了这个矩阵最主要的N个变化方向。我们利用这前N个变化方向,就可以近似这个矩阵(变换)。也就是之前说的:提取这个矩阵最重要的特征。总结一下,特征值分解可以得到特征值与特征向量,特征值表示的是这个特征到底有多重要,而特征向量表示这个特征是什么,可以将每一个特征向量理解为一个线性的子空间,我们可以利用这些线性的子空间干很多的事情。详见链接的图文解释
代码详解
# coding=utf-8 import numpy as np from numpy import * import pylab as pl def loadDataSet(fileName): fr = open(fileName) stringArr = [line.strip().split('\t') for line in fr.readlines()] datArr = [map(float,line) for line in stringArr] return mat(datArr) def pca(dataMat, topNfeat = 9999999): meanVals = mean(dataMat, axis = 0) meanRemoved = dataMat - meanVals print meanRemoved #求出协方差矩阵 covMat = cov(meanRemoved, rowvar=0) print 'covMat:', covMat #求出协方差矩阵的特征值和特征向量 eigVal, eigVects = linalg.eig(mat(covMat)) print 'eigVal:', eigVal print 'eigVects:', eigVects #升序 eigValInd = argsort(eigVal) print 'eigValInd:',eigValInd #取出topNfeat个最大的 eigValInd = eigValInd[:-(topNfeat+1):-1] print 'eigValInd:',eigValInd #作为特征项 redEigVects = eigVects[:, eigValInd] print redEigVects #以原矩阵为基降维操作 lowDataMat = meanRemoved*redEigVects #降维数据还原 reconMat = (lowDataMat * redEigVects.T) + meanVals return lowDataMat, reconMat import matplotlib.pyplot as plt fig = plt.figure() ax = fig.add_subplot(111) ax.scatter(dataMat[:,0].flatten().A[0], dataMat[:,1].flatten().A[0],marker='*',s=90, c='y') ax.scatter(recondMat[:,0].flatten().A[0], recondMat[:,1].flatten().A[0],marker='o',s=50,c='g') plt.show() def main(): dataMat = loadDataSet(r'testSet.txt') lowDMat , reconMat = pca(dataMat, 1) print shape(lowDMat) print reconMat show(dataMat, reconMat) if __name__ == '__main__': main()
测试结果:
总结
PCA让我认识到线代和概率论的重要性,还要一些老师没有提到的几何意义
优点:降低数据的复杂性,识别最重要的多个特征
缺点:不一定需要,且可能损失有用的信息
PCA可以识别数据中的主要特征,通过数据沿最大方差方向旋转坐标轴实现的,具体过程还是要好好了解线代和概率论的知识,特别是这些几何意义。
数据(最下方没东西了)
10.235186 11.32199710.122339 11.8109939.190236 8.9049439.306371 9.8473948.330131 8.34035210.152785 10.12353210.408540 10.8219869.003615 10.0392069.534872 10.0969919.498181 10.8254469.875271 9.23342610.362276 9.37689210.191204 11.2508517.720499 6.4763009.334379 8.4712687.963186 6.7313338.244973 9.0137859.569196 10.5689498.854793 9.0765369.382171 7.2408628.179055 8.9445028.267896 8.7970179.047165 8.7250688.741043 7.9013857.190216 7.8045878.081227 9.3144318.047460 5.7207807.917584 7.5432548.676942 10.1022209.210251 9.4247177.732998 9.8402027.681754 8.6098977.925863 10.0791598.261509 8.2420808.514872 7.52756110.324450 10.8044817.856710 7.9315437.858608 7.9953409.196808 6.5775989.644415 10.9350819.579833 9.0850217.888484 5.9764289.072624 9.7033448.914184 9.2985157.822869 7.08666310.538554 11.0614648.280187 8.7090128.884223 8.6701059.359927 10.5750559.078611 9.7108337.935134 8.5861738.805945 10.5751459.584316 9.61407611.269714 11.7172549.120444 9.0197747.977520 8.3139238.104648 9.4561288.617126 7.3317239.033811 9.4697068.327680 5.1220928.532272 10.1009099.295434 8.9338249.905202 9.02755910.585764 10.91273310.427584 11.5325789.072767 9.9601449.164275 8.6451219.746058 10.7170809.286072 9.3400248.188233 7.4324157.948598 8.4454197.563350 5.6561788.972405 8.8018699.980868 8.7889967.753490 7.7142487.431143 9.0328198.943403 8.35935410.481890 9.9889699.150454 10.2787608.123894 9.0603518.626164 8.4693427.354185 7.63125211.323046 11.0150328.190008 6.8607928.412598 7.6613589.258404 8.58038211.007915 11.4438818.279403 8.3470038.931149 10.10522110.239245 10.0774738.129346 7.0968778.485823 9.37356110.703640 11.6516189.500728 8.1502289.712414 9.9104459.333374 9.4075578.787865 10.1680219.238180 10.2534789.577388 8.89515010.447753 10.3182279.303944 9.2231369.883268 11.6629459.471921 10.44379210.007753 9.5799128.110298 7.1062636.964069 6.58504010.413499 9.6493098.032629 7.0532548.015549 9.16675310.462924 8.6566129.530788 10.1341309.202658 9.31422210.103241 10.2351597.849264 6.6248569.059071 7.99255510.172889 10.7247899.528439 6.4209907.190422 6.7897929.085716 9.8463289.452887 8.7353867.417322 7.3485948.468639 8.7150868.303642 9.4632319.939052 10.0267718.701989 7.5169789.737541 10.5872818.280233 7.85244410.648386 10.2592039.173893 10.5203729.135397 10.7514067.594580 8.4888338.587520 8.4634068.581887 7.8886449.448768 8.7074227.882664 7.77203010.050635 9.8597209.012078 9.5338998.770020 8.8829969.428804 9.4463068.504209 8.3196939.800003 10.9646678.069660 7.68309910.012217 10.3206448.704677 8.9181468.198722 7.2977869.868322 9.9016579.426997 11.4803539.228767 9.2629768.952359 9.5284718.186847 8.6005879.026371 8.7051439.483364 9.8070797.826587 7.97540111.197846 10.9592987.632421 8.7697458.761605 8.3093659.353670 8.7287586.466637 6.0389968.370634 9.17883010.337451 11.0756008.917679 8.2883679.076621 8.4876267.278948 4.63409710.153017 11.2191837.132603 5.8531189.338644 9.8059409.878602 9.18700010.009505 10.9245059.384438 10.6918607.535322 8.1604816.808732 8.2684698.302965 8.0750098.345379 8.3053569.517530 8.2498399.267825 9.99910910.291511 11.0326648.605909 8.7052078.331145 7.8122958.632412 10.5742878.766397 8.7121079.407070 9.7327569.709495 9.72956910.422201 11.0703606.831495 6.4667638.187122 8.4059298.523093 9.0418447.952394 6.80122010.490780 10.00146810.813791 9.8024947.861113 7.5414758.800399 8.7389747.542152 6.6128389.446981 9.3786598.281684 7.3585728.473801 8.20834311.736767 11.0220298.379578 8.7143488.313718 8.8323819.342589 10.4166597.560710 6.8896489.295344 9.7390409.176612 9.7187818.614385 10.1505219.079373 8.83979410.333289 10.9212559.453502 7.33513410.174590 10.2925009.693713 9.7936367.474925 7.75139110.107905 10.1569979.257241 7.85426610.209794 11.4101577.248050 6.43367610.150091 9.28859710.077713 10.3215008.191122 8.9315198.791469 10.2872169.229434 9.0951938.682571 8.5460057.524099 7.7097518.442410 8.3260379.364851 9.0959899.061222 7.5578997.989999 8.5553638.801275 8.86873210.351932 9.49779610.230710 10.4961519.783163 9.89140810.651481 9.4316178.387393 6.4005079.003921 7.0500038.483723 8.3148869.020501 7.5457719.329105 11.0956619.583687 9.2719298.908705 8.4075298.835406 8.0835179.736362 8.29673510.030302 9.7371788.287142 6.9934609.173211 9.3063359.026355 9.6965319.128391 9.92124711.486346 12.91077711.519458 11.4721119.027707 10.2639749.351935 8.5422009.421701 11.4032019.005687 8.1009697.015279 6.6142788.213607 8.3409488.226646 8.7189978.144753 8.36687710.133642 12.79016910.763481 10.84701610.003622 10.3377169.007955 9.7924828.670506 10.78293110.386414 9.95616210.104761 10.1230448.079502 8.3040759.945424 11.8554098.642497 9.9980669.349722 8.6903289.034991 8.8264908.738746 7.5184648.919532 9.7403129.464136 10.44458810.710057 12.66685710.042007 10.5320918.447996 7.4263639.509351 9.03051611.946359 10.5530759.981617 9.9126519.853876 9.63296710.560648 11.8817148.370952 9.9894918.323209 10.1025299.828359 11.7024628.515623 8.4267549.004363 9.62803610.529847 10.45803110.028765 10.6248809.448114 9.3132278.332617 7.3822958.323006 8.2766087.740771 8.7997508.379615 8.1461928.340764 9.1844589.863614 8.2546949.969563 9.4051349.164394 9.18212710.622098 9.7225929.592072 10.0294468.212027 7.4773669.080225 8.2444488.555774 7.8423259.958046 9.6962218.972573 9.7971289.213223 7.1284378.737239 9.38513810.333907 10.9948568.797511 8.64307511.044848 9.6231608.539260 9.09711311.582163 11.8843337.863848 7.1761996.218103 5.2835629.120602 7.2501909.001166 9.6352038.081476 8.8442249.369802 8.2309118.768925 8.6669879.841098 8.54389610.451522 9.5495119.755402 9.1175227.988961 6.8698548.872507 9.78711810.363980 10.7166086.315671 5.7659539.638879 9.2023558.588126 8.0379668.947408 9.1443869.051130 7.1951329.321709 8.38066810.146531 9.7547459.843373 8.8914379.213148 11.7006327.630078 7.2947538.093088 7.9675907.488915 6.0906528.126036 8.5864728.760350 7.26898710.201347 9.1410137.838208 7.3077006.155653 5.5639977.767841 6.2545288.425656 8.61583210.362168 10.88681510.180024 10.3789349.794665 10.0478129.970394 9.6682797.030217 7.0604719.275414 9.09573810.314911 10.4565399.259774 8.20485110.023919 9.5583078.887540 9.8667049.851608 9.4109898.710882 7.2680129.017007 10.2176737.976369 9.0009798.738332 8.6647348.344510 8.9776008.959613 12.3242409.169982 8.6246357.487451 8.1548598.706316 7.7194559.564832 8.9404038.327775 9.0445099.734032 10.1952558.021343 6.4450929.081048 11.0243977.626651 6.54926310.725858 8.5753748.731381 8.30778810.394237 10.5968747.029311 7.6588329.517907 7.50990410.394064 10.06089810.752500 9.4316019.692431 10.3321309.651897 7.8768628.592329 10.09683710.212801 10.8274969.045043 9.2655248.901643 8.03611510.794525 9.31883011.040915 12.0217468.390836 9.6724699.840166 11.22656810.806810 12.2056338.924285 10.9340568.411251 8.2896727.808891 9.6632909.733437 8.4869588.300026 7.4773748.221756 10.2783089.096867 9.6196779.410116 9.28918810.097176 9.7684709.387954 8.8448559.376134 7.7046308.231599 9.1012039.910738 10.6948558.645689 7.7645898.090245 7.1095969.253483 9.8136729.331546 8.0393869.843256 10.2087929.713131 9.2476659.259369 10.70462210.243948 9.6958836.396262 6.4563908.936289 8.7038718.750846 9.3472736.497155 4.1302519.516552 10.1648489.125766 8.8587758.374387 7.3001148.132816 7.62110710.099505 9.1591349.356477 6.8699998.112934 7.5875477.265396 6.98703111.950505 13.71510910.745959 10.8221718.893270 7.8873326.003473 4.9602197.498851 6.45133410.162072 9.9359548.732617 9.1776799.300827 9.95236011.908436 12.2568019.371215 9.1886459.943640 9.2450377.386450 7.0468198.410374 8.2932187.830419 6.4402538.263140 8.27944611.448164 12.1923638.216533 9.1866289.316128 10.0466978.156927 6.8347929.951421 11.2405989.059607 8.45844610.476339 10.5604617.548200 7.2271279.432204 7.2367059.402750 9.12641311.188095 13.8534269.520201 11.0281318.884154 9.7640718.961105 8.8331178.549663 8.86576510.111708 10.5154629.024761 9.1693687.904149 8.0487569.240995 7.7961428.126538 6.1161257.442148 7.9313359.486821 10.0913599.834289 11.6947209.009714 11.5991709.761314 11.3440836.993941 6.5629888.659524 8.4101077.685363 8.0972977.793217 6.5191098.883454 9.2573478.781821 9.2319807.946281 7.6589788.523959 10.6464809.031525 8.6496488.317140 7.7589789.192417 11.1512188.408486 8.28218210.327702 11.4590488.389687 8.5487278.642250 7.0568708.833447 9.2676388.805261 8.3202819.726211 9.0959978.477631 9.5075309.738838 9.6521108.272108 7.5826969.258089 8.4959318.334144 8.8107668.150904 6.4860327.259669 7.27015611.034180 11.51995410.705432 10.6425278.388814 7.1591378.559369 7.8462847.187988 6.5193138.811453 7.7659008.492762 7.9929418.739752 8.50290910.150752 10.4202957.062378 5.3652898.448195 7.48000010.224333 11.5927509.533795 9.2128459.519492 7.6905019.661847 10.3761897.963877 8.59719310.184486 9.1367098.505234 9.1592108.187646 8.5186909.167590 9.4059178.612162 8.51875510.970868 10.3922299.603649 9.1410959.704263 8.8301789.657506 8.1324499.337882 11.0453069.521722 9.5377648.954197 8.7281798.635658 10.3526628.910816 9.0203179.900933 9.39200210.247105 8.2896499.571690 8.1712377.388627 7.6680718.354008 10.0745909.775598 8.8356968.768913 7.9836048.330199 8.4740988.169356 9.36117210.346522 10.0864347.976144 9.2667028.429648 7.86582411.261674 11.78858710.051066 10.1124258.954626 9.7893438.382220 8.1210129.820642 9.4264418.125950 9.6950878.646465 7.2918088.190202 8.0037378.773887 7.3061758.731000 10.3004369.163098 7.8167699.456346 9.2239229.645180 9.3240538.835060 8.9669159.325950 10.9432489.941912 9.5485359.282799 10.1194889.567591 9.4621648.529019 9.7680019.314824 10.1537278.264439 8.2738608.307262 8.2140369.122041 8.6578618.404258 8.3893657.828355 8.4194339.803180 10.1082868.662439 8.5819538.883265 8.9783778.012330 8.2624519.420258 8.9748787.015415 6.3659409.888832 11.1630369.677549 10.3464318.410158 7.9128999.464147 10.7629007.067227 7.0357179.320923 10.5830899.056917 8.7712418.110004 8.38778910.310021 10.9700148.211185 8.8096278.942883 8.8407469.479958 8.3287008.973982 8.7022918.519257 8.7648559.424556 8.9569117.222919 8.1777878.257007 9.7006199.778795 9.2961348.028806 8.5759749.886464 9.9650769.090552 6.9789309.605548 10.2567519.959004 9.6102298.308701 9.5091247.748293 9.6859338.311108 9.4281149.697068 10.2179569.582991 9.4787739.167265 10.19841210.329753 10.4066028.908819 7.42878910.072908 10.3932947.992905 9.2266298.907696 7.2693668.421948 9.3429687.481399 7.22503310.358408 10.1661308.786556 10.2799439.658701 11.37936710.167807 9.4175528.653449 8.6566818.020304 8.6712708.364348 10.0040689.119183 9.7881998.405504 9.74058011.020930 11.9043509.755232 9.51571310.059542 9.5897488.727131 9.7779987.666182 6.0286428.870733 8.3675019.340446 7.7072699.919283 10.7968137.905837 8.32603410.181187 10.0898658.797328 8.9819888.466272 7.76503210.335914 12.6205399.365003 8.6091158.011017 7.24948910.923993 13.9015137.074631 7.5587209.824598 8.8512978.861026 8.37085710.127296 10.86153510.548377 10.8556958.880470 7.9487618.901619 9.6747057.813710 9.24691210.128808 10.56066811.096699 10.9116448.551471 6.8715148.907241 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8.3957009.532945 9.8506969.459384 9.3842138.982743 8.21706210.107798 8.79077210.563574 9.0448908.278963 9.5187908.734960 10.4941299.597940 9.53089510.025478 9.50827010.335922 10.9740638.404390 8.1467487.108699 6.0384698.873951 7.4742278.731459 8.1544558.795146 7.5346876.407165 6.8103529.979312 10.2874308.786715 8.39673610.753339 10.36056710.508031 10.32197610.636925 10.19379710.614322 11.2154208.916411 8.9652868.112756 8.30476910.833109 10.4975428.319758 9.7276919.945336 11.82009710.150461 9.91471510.185024 10.3887229.793569 9.07995510.590128 11.8115968.505584 6.88428210.461428 10.7454398.755781 9.4184277.488249 7.17207210.238905 10.4286599.887827 10.4278218.529971 8.8382178.375208 10.2428378.901724 8.3983048.607694 9.1731988.691369 9.9642619.584578 9.64154610.265792 11.4050787.592968 6.6833558.692791 9.3890317.589852 6.00579310.550386 11.7365848.578351 7.2270557.526931 6.8751348.577081 9.8771159.272136 11.05092810.300809 10.6530598.642013 9.0066819.720491 10.2652029.029005 9.6469288.736201 7.9756038.672886 9.0707598.370633 8.4121709.483776 9.1833416.790842 7.5949929.842146 10.1568109.563336 7.9625328.724669 9.8707329.012145 9.1713269.116948 9.7911676.219094 7.9884209.468422 8.3599758.825231 8.4752089.572224 9.6964289.609128 8.4881759.428590 10.4689988.293266 8.6177019.423584 10.3556889.240796 9.51722810.915423 13.02625210.854684 11.1308669.226816 9.3917969.580264 10.3592357.289907 6.8982089.338857 10.3740259.523176 11.33219010.162233 10.3573968.873930 9.2073988.607259 7.7948048.852325 8.2157978.077272 6.5010428.169273 8.2696136.806421 7.5444238.793151 9.69154911.640981 11.3657029.544082 11.5765459.009266 9.6055969.726552 9.4267199.495888 10.6266248.683982 9.3378648.322105 8.6310998.887895 8.6449318.662659 11.3730259.263321 7.5360167.802624 7.1716258.773183 8.5615658.730443 10.1975968.942915 7.7583838.057618 8.7749968.112081 8.20234910.378884 12.1037559.248876 8.6372499.739599 9.7085768.126345 8.2784878.894788 7.9661179.683165 9.01922110.886957 12.0538439.668852 10.9021327.486692 6.4711388.794850 9.1736098.835915 8.2967279.443984 11.3753448.696621 6.4345809.645560 9.2337229.623857 7.91559010.840632 12.6202687.298135 7.3561419.639644 8.9023899.849802 7.68262410.609964 10.2596159.768229 11.3828117.646351 7.57184910.230300 9.4708598.224402 8.4968666.879671 8.3936487.976247 8.6672219.183268 8.69455011.471853 12.78628010.428349 10.6157268.090828 5.9025049.738627 8.4857928.139709 8.3963339.508055 8.9905298.857260 8.4977328.902558 7.0144339.660607 11.0408338.772221 10.51215011.020038 9.3541347.918527 7.7420627.630835 7.75626011.043272 11.0416139.299376 8.6741579.795087 8.4318379.415683 8.3121017.942037 6.9429139.724790 11.76649610.222032 11.5508768.894163 8.3060208.394309 8.0704209.012776 6.8805489.661093 10.1389219.896472 9.7623729.135628 8.7599288.762656 10.3060288.602473 8.86195610.085297 10.46477410.644983 10.9457679.034571 8.3916688.602920 8.5019448.224766 7.4027588.755050 9.4310859.669937 8.64104910.693530 10.2871249.462806 7.6111539.287707 10.08236310.941260 10.7837289.263080 7.91332810.167111 10.2253388.783830 9.4653458.958624 8.6621369.841649 9.9267817.205691 6.7906388.629089 9.1354617.469440 8.4504428.179133 7.7904348.083984 7.8755209.271300 8.1353598.652349 8.2543977.983920 6.6096847.836860 9.7852387.418535 7.0112568.458288 10.0953649.387605 9.7269118.663951 8.20670510.146507 11.6985778.937103 10.99092411.218687 11.1419458.363142 9.1069367.877643 7.1229229.620978 9.9056899.509649 10.7732096.748743 6.7053859.300919 8.0850299.332257 9.8187917.898610 8.3666439.841914 9.4806756.920484 8.9595018.544713 9.5631368.162266 6.7152778.659552 9.28200810.673398 13.1748249.024000 10.3792388.183292 6.64757210.544919 10.6496027.201266 6.5296059.557407 11.0968218.304605 6.9409299.742855 9.92089710.024587 9.64522210.002296 9.9989408.965876 8.6654197.823136 6.9495728.125088 7.6540656.569589 6.04686310.195497 8.68912911.730011 10.3742218.739105 7.4575719.820059 10.2785269.547456 10.3981988.375072 8.4163028.889533 8.3089298.861201 9.29040812.677687 12.7884639.100735 8.6205377.728350 6.3282197.955373 8.3550288.733352 8.64541410.257527 11.1918139.246413 9.4970149.745302 9.6420357.785652 8.1476217.431673 8.5663998.654384 8.4667018.475392 6.7446779.968440 10.76519210.163616 10.80696310.238135 10.0366369.902889 10.7467309.523850 8.7497089.214363 9.1491789.266040 10.8415028.494292 7.77094210.821158 10.4101928.645888 7.9703089.885204 10.0980809.084990 10.8863499.277874 8.8714498.135131 7.1370647.917379 9.0805229.685586 8.8228508.558141 7.8481129.502917 10.0612556.409004 5.16477410.149235 10.5799517.847304 8.4113518.846930 6.8199398.675153 9.4111479.476276 9.06150811.099184 10.6442638.792411 10.3794058.400418 7.0727068.555713 7.9238058.024763 8.4269938.642696 10.4534127.906117 7.9204088.793393 9.7228788.280364 7.6698549.387766 9.7062459.626853 10.76249910.163631 10.9190079.375543 11.5135249.309440 8.57569910.055329 10.2972558.706241 9.09717210.032934 11.95189710.812974 11.31143510.352603 10.8198658.276870 9.0554038.397389 7.9444349.371741 10.39579010.825710 10.1440999.158483 11.38538210.658639 11.3898568.091762 6.63103910.734892 10.05459811.535880 11.6049129.799077 11.3716778.478725 9.0784559.399902 8.9477447.305377 8.1449737.613377 6.66879810.681308 10.8308459.973855 10.0041339.369918 7.8554338.838223 7.4290339.521831 10.6239309.724419 10.4474528.890224 9.2759239.932763 11.58995310.839337 9.0512508.497708 7.5217018.440236 8.7056709.063566 9.7557448.449647 8.9294858.554576 8.06323110.348606 10.5507185.985254 5.1868449.931937 10.1755829.854922 9.2013939.114580 9.13421510.334899 8.543604
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