2010-02-23 73 views
7

我正在使用e1071软件包中的支持向量机对我的数据进行分类,并希望可视化机器实际进行分类的方式。但是,使用plot.svm函数时,出现无法解析的错误。绘制SVM分类图的错误

脚本:

library("e1071") 

data <-read.table("2010223_11042_complete") 
names(data) <- c("Class","V1", "V2") 

model <- svm(Class~.,data, type = "C-classification", kernel = "linear") 
plot(model,data,fill=TRUE, grid=200, svSymbol=4, dataSymbol=1, color.palette=terrain.colors) 

输出:

plot(model,data,fill=TRUE, grid=200, svSymbol=4, dataSymbol=1, color.palette=terrain.colors) 
Error in rect(0, levels[-length(levels)], 1, levels[-1L], col = col) : 
    cannot mix zero-length and non-zero-length coordinates 

回溯:我(4488线长)数据文件的

traceback() 
4: rect(0, levels[-length(levels)], 1, levels[-1L], col = col) 
3: filled.contour(xr, yr, matrix(as.numeric(preds), nr = length(xr), 
     byrow = TRUE), plot.axes = { 
     axis(1) 
     axis(2) 
     colind <- as.numeric(model.response(model.frame(x, data))) 
     dat1 <- data[-x$index, ] 
     dat2 <- data[x$index, ] 
     coltmp1 <- symbolPalette[colind[-x$index]] 
     coltmp2 <- symbolPalette[colind[x$index]] 
     points(formula, data = dat1, pch = dataSymbol, col = coltmp1) 
     points(formula, data = dat2, pch = svSymbol, col = coltmp2) 
    }, levels = 1:(length(levels(preds)) + 1), key.axes = axis(4, 
     1:(length(levels(preds))) + 0.5, labels = levels(preds), 
     las = 3), plot.title = title(main = "SVM classification plot", 
     xlab = names(lis)[2], ylab = names(lis)[1]), ...) 
2: plot.svm(model, data, fill = TRUE, grid = 200, svSymbol = 4, 
     dataSymbol = 1, color.palette = terrain.colors) 
1: plot(model, data, fill = TRUE, grid = 200, svSymbol = 4, 
     dataSymbol = 1, color.palette = terrain.colors) 

部分:

-1 0 23.532 
+1 1 61.1157 
+1 1 61.1157 
+1 1 61.1157 
-1 1 179.03 
-1 0 17.0865 
-1 0 27.6201 
-1 0 17.0865 
-1 0 27.6201 
-1 1 89.6398 
-1 0 42.7418 
-1 1 89.6398 

由于我刚刚开始使用R,我不知道这意味着什么,我该如何处理它,也没有在其他地方找到任何有用的东西。

回答

4

没有被确定到底是什么导致了问题,我会用这样的尝试将Class列转换为一个因子(所以在定义类型为C-classification将不再是必要的):

data$Class <- as.factor(data$Class) 

或在一步:

model <- svm(as.factor(Class)~.,data, kernel = "linear") 
+0

谢谢你的家伙。奇迹般有效。就像你建议的那样,我将Class列转换为一个因子,并在svm的调用中删除了'type'参数。错误消失了。 – user655423 2010-02-23 12:53:36