www.pudn.com > CsharpSVM.rar > svm_train.cs, change:2004-06-06,size:8571b
using System; using libsvm; /* Conversion notes (Andrew Poh): * Removed nested call of Streamreader constructor - original Java used BufferedReader * wrapped around FileReader. * * Removed SupportClass because duplicated in svm library. * * Replaced System.Console.arraycopy() with Array.Copy - this stemmed from a lousy * conversion of System.arraycopy(). * * Replaced System.Math.Max() with System.Math.Max(). * * Replaced (ArrayList)vx.addElement() in read_problem() with Add(). */ class svm_train { private svm_parameter param; // set by parse_command_line private svm_problem prob; // set by read_problem private svm_model model; private System.String input_file_name; // set by parse_command_line private System.String model_file_name; // set by parse_command_line private System.String error_msg; private int cross_validation = 0; private int nr_fold; private static void exit_with_help() { System.Console.Out.Write("Usage: svm_train [options] training_set_file [model_file]\n" + "options:\n" + "-s svm_type : set type of SVM (default 0)\n" + " 0 -- C-SVC\n" + " 1 -- nu-SVC\n" + " 2 -- one-class SVM\n" + " 3 -- epsilon-SVR\n" + " 4 -- nu-SVR\n" + "-t kernel_type : set type of kernel function (default 2)\n" + " 0 -- linear: u'*v\n" + " 1 -- polynomial: (gamma*u'*v + coef0)^degree\n" + " 2 -- radial basis function: exp(-gamma*|u-v|^2)\n" + " 3 -- sigmoid: tanh(gamma*u'*v + coef0)\n" + "-d degree : set degree in kernel function (default 3)\n" + "-g gamma : set gamma in kernel function (default 1/k)\n" + "-r coef0 : set coef0 in kernel function (default 0)\n" + "-c cost : set the parameter C of C-SVC, epsilon-SVR, and nu-SVR (default 1)\n" + "-n nu : set the parameter nu of nu-SVC, one-class SVM, and nu-SVR (default 0.5)\n" + "-p epsilon : set the epsilon in loss function of epsilon-SVR (default 0.1)\n" + "-m cachesize : set cache memory size in MB (default 40)\n" + "-e epsilon : set tolerance of termination criterion (default 0.001)\n" + "-h shrinking: whether to use the shrinking heuristics, 0 or 1 (default 1)\n" + "-b probability_estimates: whether to train a SVC or SVR model for probability estimates, 0 or 1 (default 0)\n" + "-wi weight: set the parameter C of class i to weight*C, for C-SVC (default 1)\n" + "-v n: n-fold cross validation mode\n"); System.Environment.Exit(1); } private void do_cross_validation() { int i; int total_correct = 0; double total_error = 0; double sumv = 0, sumy = 0, sumvv = 0, sumyy = 0, sumvy = 0; double[] target = new double[prob.l]; svm.svm_cross_validation(prob, param, nr_fold, target); if (param.svm_type == svm_parameter.EPSILON_SVR || param.svm_type == svm_parameter.NU_SVR) { for (i = 0; i < prob.l; i++) { double y = prob.y[i]; double v = target[i]; total_error += (v - y) * (v - y); sumv += v; sumy += y; sumvv += v * v; sumyy += y * y; sumvy += v * y; } System.Console.Out.Write("Cross Validation Mean squared error = " + total_error / prob.l + "\n"); System.Console.Out.Write("Cross Validation Squared correlation coefficient = " + (((prob.l * sumvy - sumv * sumy) * (prob.l * sumvy - sumv * sumy)) / ((prob.l * sumvv - sumv * sumv) * (prob.l * sumyy - sumy * sumy))) + "\n"); } else for (i = 0; i < prob.l; i++) if (target[i] == prob.y[i]) ++total_correct; System.Console.Out.Write("Cross Validation Accuracy = " + 100.0 * total_correct / prob.l + "%\n"); } private void run(System.String[] argv) { parse_command_line(argv); read_problem(); error_msg = svm.svm_check_parameter(prob, param); if ((System.Object) error_msg != null) { System.Console.Error.Write("Error: " + error_msg + "\n"); System.Environment.Exit(1); } if (cross_validation != 0) { do_cross_validation(); } else { model = svm.svm_train(prob, param); svm.svm_save_model(model_file_name, model); } } [STAThread] public static void Main(System.String[] argv) { svm_train t = new svm_train(); t.run(argv); } private static double atof(System.String s) { return System.Double.Parse(s); } private static int atoi(System.String s) { return System.Int32.Parse(s); } private void parse_command_line(System.String[] argv) { int i; param = new svm_parameter(); // default values param.svm_type = svm_parameter.C_SVC; param.kernel_type = svm_parameter.RBF; param.degree = 3; param.gamma = 0; // 1/k param.coef0 = 0; param.nu = 0.5; param.cache_size = 40; param.C = 1; param.eps = 1e-3; param.p = 0.1; param.shrinking = 1; param.probability = 0; param.nr_weight = 0; param.weight_label = new int[0]; param.weight = new double[0]; // parse options for (i = 0; i < argv.Length; i++) { if (argv[i][0] != '-') break; ++i; switch (argv[i - 1][1]) { case 's': param.svm_type = atoi(argv[i]); break; case 't': param.kernel_type = atoi(argv[i]); break; case 'd': param.degree = atof(argv[i]); break; case 'g': param.gamma = atof(argv[i]); break; case 'r': param.coef0 = atof(argv[i]); break; case 'n': param.nu = atof(argv[i]); break; case 'm': param.cache_size = atof(argv[i]); break; case 'c': param.C = atof(argv[i]); break; case 'e': param.eps = atof(argv[i]); break; case 'p': param.p = atof(argv[i]); break; case 'h': param.shrinking = atoi(argv[i]); break; case 'b': param.probability = atoi(argv[i]); break; case 'v': cross_validation = 1; nr_fold = atoi(argv[i]); if (nr_fold < 2) { System.Console.Error.Write("n-fold cross validation: n must >= 2\n"); exit_with_help(); } break; case 'w': ++param.nr_weight; { int[] old = param.weight_label; param.weight_label = new int[param.nr_weight]; Array.Copy(old, 0, param.weight_label, 0, param.nr_weight - 1); } { double[] old = param.weight; param.weight = new double[param.nr_weight]; Array.Copy(old, 0, param.weight, 0, param.nr_weight - 1); } param.weight_label[param.nr_weight - 1] = atoi(argv[i - 1].Substring(2)); param.weight[param.nr_weight - 1] = atof(argv[i]); break; default: System.Console.Error.Write("unknown option\n"); exit_with_help(); break; } } // determine filenames if (i >= argv.Length) exit_with_help(); input_file_name = argv[i]; if (i < argv.Length - 1) model_file_name = argv[i + 1]; else { int p = argv[i].LastIndexOf((System.Char) '/'); ++p; // whew... model_file_name = argv[i].Substring(p) + ".model"; } } // read in a problem (in svmlight format) private void read_problem() { /* UPGRADE_TODO: Expected value of parameters of constructor * 'java.io.BufferedReader.BufferedReader' are different in the equivalent in .NET. * 'ms-help://MS.VSCC.2003/commoner/redir/redirect.htm?keyword="jlca1092"' */ System.IO.StreamReader fp = new System.IO.StreamReader(input_file_name); System.Collections.ArrayList vy = new System.Collections.ArrayList(10); System.Collections.ArrayList vx = new System.Collections.ArrayList(10); int max_index = 0; while (true) { System.String line = fp.ReadLine(); if ((System.Object) line == null) break; SupportClass.Tokenizer st = new SupportClass.Tokenizer(line, " \t\n\r\f:"); vy.Add(st.NextToken()); int m = st.Count / 2; svm_node[] x = new svm_node[m]; for (int j = 0; j < m; j++) { x[j] = new svm_node(); x[j].index = atoi(st.NextToken()); x[j].value_Renamed = atof(st.NextToken()); } if (m > 0) max_index = System.Math.Max(max_index, x[m - 1].index); vx.Add(x); } prob = new svm_problem(); prob.l = vy.Count; prob.x = new svm_node[prob.l][]; for (int i = 0; i < prob.l; i++) prob.x[i] = (svm_node[]) vx[i]; prob.y = new double[prob.l]; for (int i = 0; i < prob.l; i++) prob.y[i] = atof((System.String) vy[i]); if (param.gamma == 0) param.gamma = 1.0 / max_index; fp.Close(); } }