Felomeng翻译：libsvm2.88之“svm-train”的使用

<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="">语法：</span><span style=""><span style="font-family: Times New Roman;">svm-train [</span></span><span style="">参数表</span><span style=""><span style="font-family: Times New Roman;">] </span></span><span style="">训练数据集文件</span><span style=""><span style="font-family: Times New Roman;"> [</span></span><span style="">模型文件</span><span style=""><span style="font-family: Times New Roman;">] </span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style=""><span style="font-size: small;">参数：</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-s </span></span><span style="">支持向量机类型：支持向量机类型集合（默认值</span><span style=""><span style="font-family: Times New Roman;">0</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">0 -- C-SVC</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">1 -- nu-SVC</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">2 -- one-class SVM</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">3 -- epsilon-SVR</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">4 -- nu-SVR</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-t </span></span><span style="">内核类型：内核函数集合（默认值</span><span style=""><span style="font-family: Times New Roman;">2</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">0 -- </span></span><span style="">线性函数：</span><span style=""><span style="font-family: Times New Roman;">u'*v</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">1 --</span></span><span class="trans"><span style="">多项式函数：</span></span><span style=""><span style="font-family: Times New Roman;">(gamma*u'*v + coef0)^degree</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">2 --</span></span><span style="">径向基函数：</span><span style=""><span style="font-family: Times New Roman;">exp(-gamma*|u-v|^2)</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">3 – sigmoid</span></span><span style="">函数：</span><span style=""><span style="font-family: Times New Roman;">tanh(gamma*u'*v + coef0)</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="font-family: Times New Roman;"><span lang="EN-US"><span style=""> </span></span><span style="">4 – </span></span><span style="">预先计算好的内核函数</span><span style=""><span style="font-family: Times New Roman;"> (</span></span><span style="">训练文件中的内核数值</span><span style=""><span style="font-family: Times New Roman;">)</span></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-d degree</span></span><span style="">值：设定内核函数的degree值（默认值</span><span style=""><span style="font-family: Times New Roman;">3</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-g gamma</span></span><span style="">值：设定内核函数的</span><span style=""><span style="font-family: Times New Roman;">gamma</span></span><span style="">值（默认值</span><span style=""><span style="font-family: Times New Roman;">1/k</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-r coef0</span></span><span style="">值：设定内核函数的</span><span style=""><span style="font-family: Times New Roman;">coef0</span></span><span style="">值（默认值</span><span style=""><span style="font-family: Times New Roman;">0</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-c cost</span></span><span style="">值：设定</span><span style=""><span style="font-family: Times New Roman;">C-SVC</span></span><span style="">、</span><span style=""><span style="font-family: Times New Roman;">epsilon-SVR</span></span><span style="">、和</span><span style=""><span style="font-family: Times New Roman;">nu-SVR</span></span><span style="">中的参数</span><span style=""><span style="font-family: Times New Roman;">C</span></span><span style="">的值（默认值</span><span style=""><span style="font-family: Times New Roman;">1</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-n nu</span></span><span style="">值：设定</span><span style=""><span style="font-family: Times New Roman;">nu-SVC</span></span><span style="">、</span><span style=""><span style="font-family: Times New Roman;">one-class SVM</span></span><span style="">、和</span><span style=""><span style="font-family: Times New Roman;">nu-SVR</span></span><span style="">中的参数</span><span style=""><span style="font-family: Times New Roman;">nu</span></span><span style="">的值（默认值</span><span style=""><span style="font-family: Times New Roman;">0.5</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-p epsilon</span></span><span style="">值：设定</span><span style=""><span style="font-family: Times New Roman;">epsilon-SVR</span></span><span style="">中损失函数的</span><span style=""><span style="font-family: Times New Roman;">epsilon</span></span><span style="">值（默认值</span><span style=""><span style="font-family: Times New Roman;">0.1</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-m </span></span><span style="">缓存大小：设定缓存内存大小，以</span><span style=""><span style="font-family: Times New Roman;">MB</span></span><span style="">为单位（默认值</span><span style=""><span style="font-family: Times New Roman;">100</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-e epsilon</span></span><span style="">值：设定结束条件（默认值</span><span style=""><span style="font-family: Times New Roman;">0.001</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-h </span></span><span style="">压缩：是否启用启发式压缩，值为</span><span style=""><span style="font-family: Times New Roman;">0</span></span><span style="">或</span><span style=""><span style="font-family: Times New Roman;">1</span></span><span style="">（默认</span><span style=""><span style="font-family: Times New Roman;">1</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-b </span></span><span style="">概率期望：在训练</span><span style=""><span style="font-family: Times New Roman;">SVC</span></span><span style="">或</span><span style=""><span style="font-family: Times New Roman;">SVR</span></span><span style="">模型时是否启用概率期望，值为</span><span style=""><span style="font-family: Times New Roman;">0</span></span><span style="">或</span><span style=""><span style="font-family: Times New Roman;">1</span></span><span style="">（默认值</span><span style=""><span style="font-family: Times New Roman;">0</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-wi </span></span><span style="">权重：设定</span><span style=""><span style="font-family: Times New Roman;">C-SVC</span></span><span style="">中类</span><span style=""><span style="font-family: Times New Roman;">i</span></span><span style="">的参数</span><span style=""><span style="font-family: Times New Roman;">C</span></span><span style="">为权重</span><span style=""><span style="font-family: Times New Roman;">*C</span></span><span style="">（默认值</span><span style=""><span style="font-family: Times New Roman;">1</span></span><span style="">）</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-v n</span></span><span style="">：</span><span style=""><span style="font-family: Times New Roman;">n</span></span><span style="">重交叉验证模式</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;"></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style=""><span style="font-family: Times New Roman;">-g</span></span><span style="">参数的</span><span style=""><span style="font-family: Times New Roman;">k</span></span><span style="">值表示输入数据的属性数量。</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;"></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="">参数</span><span style=""><span style="font-family: Times New Roman;">-v</span></span><span style="">随机切分数据为</span><span style=""><span style="font-family: Times New Roman;">n</span></span><span style="">个部分，然后计算它们之间交叉验证的精确度</span><span style=""><span style="font-family: Times New Roman;">/</span></span><span style="">平均方差。</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;"></span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><span style="font-size: small;"><span style="">输出内容的含义参见</span><span style=""><span style="font-family: Times New Roman;">libsvm</span></span><span style="">常见问题（</span><span style=""><span style="font-family: Times New Roman;">FAQ</span></span><span style="">）。</span></span></p>