Hi What about something like
p+geom_ribbon(aes(ymin = slope_1*x + intercept_1 - 1/w[2], ymax = slope_1*x + intercept_1 + 1/w[2], fill = "grey70", alpha=0.1)) Cheers Petr > -----Original Message----- > From: Luigi Marongiu <marongiu.lu...@gmail.com> > Sent: Friday, October 23, 2020 11:11 AM > To: PIKAL Petr <petr.pi...@precheza.cz> > Cc: r-help <r-help@r-project.org> > Subject: Re: [R] How to shade area between lines in ggplot2 > > also from this site: https://plotly.com/ggplot2/geom_ribbon/ > I get the answer is geom_ribbon but I am still missing something ``` #! plot > p > = ggplot(data = trainset, aes(x=x, y=y, color=z)) + > geom_point() + scale_color_manual(values = c("red", "blue")) # show > support vectors df_sv = trainset[svm_model$index, ] p = p + > geom_point(data = df_sv, aes(x=x, y=y), > color="purple", size=4, alpha=0.5) # show hyperplane > (decision > boundaries are off set by 1/w[2]) w = t(svm_model$coefs) %*% > svm_model$SV # %*% = matrix multiplication > slope_1 = -w[1]/w[2] > intercept_1 = svm_model$rho / w[2] > p = p + geom_abline(slope = slope_1, intercept = intercept_1, col = > "royalblue4") > p = p + geom_ribbon(aes(ymin=intercept_1 - 1/w[2], > ymax=intercept_1 + 1/w[2], > x=x, fill = "band"), alpha = 0.3) + > scale_fill_manual("",values="grey12") > ``` > > On Fri, Oct 23, 2020 at 10:26 AM PIKAL Petr <petr.pi...@precheza.cz> wrote: > > > > Hi > > > > Did you try google? I got several answers using your question > > > > e.g. > > https://stackoverflow.com/questions/54687321/fill-area-between-lines-u > > sing-g > > gplot-in-r > > > > Cheers > > Petr > > > > > -----Original Message----- > > > From: R-help <r-help-boun...@r-project.org> On Behalf Of Luigi > > > Marongiu > > > Sent: Friday, October 23, 2020 9:59 AM > > > To: r-help <r-help@r-project.org> > > > Subject: [R] How to shade area between lines in ggplot2 > > > > > > Hello, > > > I am running SVM and showing the results with ggplot2. The results > > > include the decision boundaries, which are two dashed lines parallel > > > to a solid > > line. I > > > would like to remove the dashed lines and use a shaded area instead. > > > How can I do that? > > > Here is the code I wrote.. > > > ``` > > > library(e1071) > > > library(ggplot2) > > > > > > set.seed(100) > > > x1 = rnorm(100, mean = 0.2, sd = 0.1) > > > y1 = rnorm(100, mean = 0.7, sd = 0.1) > > > y2 = rnorm(100, mean = 0.2, sd = 0.1) > > > x2 = rnorm(100, mean = 0.75, sd = 0.1) df = data.frame(x = c(x1,x2), > > > y=c(y1,y2), > > > z=c(rep(0, length(x1)), rep(1, length(x2)))) df$z = > > factor(c(rep(0, > > > length(x1)), rep(1, length(x2)))) df[, "train"] <- > > > ifelse(runif(nrow(df)) > > < 0.8, 1, 0) > > > trainset <- df[df$train == 1, ] testset <- df[df$train == 0, ] > > > trainColNum > > <- > > > grep("train", names(df)) trainset <- trainset[, -trainColNum] > > > testset <- > > testset[, > > > -trainColNum] head(trainset); str(df) > > > > > > svm_model<- svm(z ~ ., > > > data = trainset, > > > type = "C-classification", > > > kernel = "linear", > > > scale = FALSE) > > > > > > #! plot > > > p = ggplot(data = trainset, aes(x=x, y=y, color=z)) + > > > geom_point() + scale_color_manual(values = c("red", "blue")) # > > > show decision boundaries w = t(svm_model$coefs) %*% svm_model$SV > # > > > %*% = matrix multiplication > > > slope_1 = -w[1]/w[2] > > > intercept_1 = svm_model$rho / w[2] > > > p = p + geom_abline(slope = slope_1, intercept = intercept_1) ### > > > here we > > go: > > > can I use a shaded area between these two lines? ### p = p + > > > geom_abline(slope = slope_1, intercept = intercept_1 - 1/w[2], > > > linetype = "dashed") + > > > geom_abline(slope = slope_1, intercept = intercept_1 + 1/w[2], > > > linetype = "dashed") > > > print(p) > > > > > > ``` > > > > > > Thank you > > > > > > -- > > > Best regards, > > > Luigi > > > > > > ______________________________________________ > > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > > https://stat.ethz.ch/mailman/listinfo/r-help > > > PLEASE do read the posting guide http://www.R-project.org/posting- > > > guide.html and provide commented, minimal, self-contained, > > > reproducible code. > > > > -- > Best regards, > Luigi
______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
