Nested facet_wrap() in ggplot2 - r

Say I have these data:
set.seed(100)
mydf<-
data.frame(
day = rep(1:5, each=20),
id = rep(LETTERS[1:4],25),
x = runif(100),
y = sample(1:2,100,T)
)
If I just want to plot all five days of id=="A" using facet_wrap(), we do like this:
ggplot(mydf[mydf$id=="A",], aes(x,y)) +
geom_tile() +
facet_wrap(~day,ncol=1)
Gives:
But, if I want to plot four of these next to each other automatically in a 2x2 grid (i.e. showing A,B,C,D), is that possible using a nested facet? I tried doing multiple variables in the function like this:
ggplot(mydf, aes(x,y)) +
geom_tile() +
facet_wrap(~ day+id)
but this gives this:
I'm looking for a nested approach. Five faceted rows by day in each panel with each plot in columns/rows by id. Obviously for a small number of plots I could save individually and arrange with grid.arrange etc., but in the real data I have many plots so want to automate if possible.
EDIT:
In response to comment - this is the sort of desired output:

try this,
p <- ggplot(mydf, aes(x,y)) +
geom_tile() +
facet_wrap(~ day, ncol=1)
library(plyr)
lp <- dlply(mydf, "id", function(d) p %+% d + ggtitle(unique(d$id)))
library(gridExtra)
grid.arrange(grobs=lp, ncol=2)

Here is a quick attempt using the multiplot function found here
ids = levels(as.factor(mydf$id))
p = vector("list", length(ids))
names(p) = ids
for(i in 1:length(ids)){
p[[i]] = ggplot(mydf[mydf$id == ids[i],], aes(x,y)) + geom_tile() + ggtitle(paste(ids[i])) + facet_wrap(~day, ncol=1)
}
multiplot(p$A, p$B, p$C, p$D, cols = 2)

Related

Why does R behave differently when parsing parameters of plotting?

I am attempting to plot multiple time series variables on a single line chart using ggplot. I am using a data.frame which contains n time series variables, and a column of time periods. Essentially, I want to loop through the data.frame, and add exactly n goem_lines to a single chart.
Initially I tried using the following code, where;
df = data.frame containing n time series variables, and 1 column of time periods
wid = n (number of time series variables)
p <- ggplot() +
scale_color_manual(values=c(colours[1:wid]))
for (i in 1:wid) {
p <- p + geom_line(aes(x=df$Time, y=df[,i], color=var.lab[i]))
}
ggplotly(p)
However, this only produces a plot of the final time series variable in the data.frame. I then investigated further, and found that following sets of code produce completely different results:
p <- ggplot() +
scale_color_manual(values=c(colours[1:wid]))
i = 1
p = p + geom_line(aes(x=df$Time, y=df[,i], color=var.lab[i]))
i = 2
p = p + geom_line(aes(x=df$Time, y=df[,i], color=var.lab[i]))
i = 3
p = p + geom_line(aes(x=df$Time, y=df[,i], color=var.lab[i]))
ggplotly(p)
Plot produced by code above
p <- ggplot() +
scale_color_manual(values=c(colours[1:wid]))
p = p + geom_line(aes(x=df$Time, y=df[,1], color=var.lab[1]))
p = p + geom_line(aes(x=df$Time, y=df[,2], color=var.lab[2]))
p = p + geom_line(aes(x=df$Time, y=df[,3], color=var.lab[3]))
ggplotly(p)
Plot produced by code above
In my mind, these two sets of code are identical, so could anyone explain why they produce such different results?
I know this could probably be done quite easily using autoplot, but I am more interested in the behavior of these two snipits of code.
What you're trying to do is a 'hack' way by plotting multiple lines, but it's not ideal in ggplot terms. To do it successfully, I'd use aes_string. But it's a hack.
df <- data.frame(Time = 1:20,
Var1 = rnorm(20),
Var2 = rnorm(20, mean = 0.5),
Var3 = rnorm(20, mean = 0.8))
vars <- paste0("Var", 1:3)
col_vec <- RColorBrewer::brewer.pal(3, "Accent")
library(ggplot2)
p <- ggplot(df, aes(Time))
for (i in 1:length(vars)) {
p <- p + geom_line(aes_string(y = vars[i]), color = col_vec[i], lwd = 1)
}
p + labs(y = "value")
How to do it properly
To make this plot more properly, you need to pivot the data first, so that each aesthetic (aes) is mapped to a variable in your data frame. That means we need a single variable to be color in our data frame. Hence, we pivot_longer and plot again:
library(tidyr)
df_melt <- pivot_longer(df, cols = Var1:Var3, names_to = "var")
ggplot(df_melt, aes(Time, value, color = var)) +
geom_line(lwd = 1) +
scale_color_manual(values = col_vec)

ggplot2() and gridExtra() - how to get uniformity between multi-plots and single plots?

I've got five data frames, df1-df5.
I'd like to make five scatter plots, one for each data frame, using ggplot2(). I'd like four of the plots (df1p-df4p) to be grouped together, but the fifth one (df5p) to be separate.
I've managed to group df1p-df4p together. The problem's that the font and the overall look of the dfp5 plot is different from the joint df1p-df4p plots. I'd like some uniformity, so I'd like the df5p plot to be of similar size, font, and format as one of the plots in the df1p-df4p grouping.
Any help would be much appreciated.
Starting point (df1-df5):
df1 <- data.frame(var1=c(1.23,4.23,10.32),var2=c(1,6,18.7))
df2 <- data.frame(var3=c(3.32,5.34,18.45),var4=c(3.54,9.43,17.34))
df3 <- data.frame(var5=c(3.43,19.32,1.23),var6=c(2.32,19.12,4.23))
df4 <- data.frame(var7=c(4.54,2.23,19.32),var8=c(1.54,6.43,19.4))
df5 <- data.frame(var9=c(5.43,1.23,19.54),var10=c(1.23,8.43,19.9))
Current code:
library(gridExtra)
library(ggplot2)
df1p <- ggplot(df1, aes(x=var1, y=var2)) + geom_point(shape=2) + ggtitle("df1 plot")
df2p <- ggplot(df2, aes(x=var3, y=var4)) + geom_point(shape=2) + ggtitle("df2 plot")
df3p <- ggplot(df3, aes(x=var5, y=var6)) + geom_point(shape=2) + ggtitle("df3 plot")
df4p <- ggplot(df4, aes(x=var7, y=var8)) + geom_point(shape=2) + ggtitle("df4 plot")
df5p <- ggplot(df5, aes(x=var9, y=var10)) + geom_point(shape=2) + ggtitle("df5 plot")
df1to4p<- grid.arrange(df1p,df2p,df3p,df4p, ncol=2)
Here's an example of laying out the plots in a way that results in plots of similar size. I've also taken the liberty of putting your data frames and plots into lists to shorten the code:
library(gridExtra)
library(ggplot2)
# List of data frames
dl = mget(paste0("df",1:5))
# List of plots
pl = lapply(names(dl), function(dat) {
v = names(dl[[dat]])
ggplot(dl[[dat]], aes_string(x=v[1], y=v[2])) +
geom_point(shape=2) +
ggtitle(paste(dat, "plot"))
})
png("4plots.png", 400, 400)
grid.arrange(grobs=pl[1:4], ncol=2)
dev.off()
png("5thPlot.png", 200, 200)
pl[[5]]
dev.off()

Align multiple ggplot graphs with and without legends [duplicate]

This question already has answers here:
Align multiple plots in ggplot2 when some have legends and others don't
(6 answers)
Closed 5 years ago.
I'm trying to use ggplot to draw a graph comparing the absolute values of two variables, and also show the ratio between them. Since the ratio is unitless and the values are not, I can't show them on the same y-axis, so I'd like to stack vertically as two separate graphs with aligned x-axes.
Here's what I've got so far:
library(ggplot2)
library(dplyr)
library(gridExtra)
# Prepare some sample data.
results <- data.frame(index=(1:20))
results$control <- 50 * results$index
results$value <- results$index * 50 + 2.5*results$index^2 - results$index^3 / 8
results$ratio <- results$value / results$control
# Plot absolute values
plot_values <- ggplot(results, aes(x=index)) +
geom_point(aes(y=value, color="value")) +
geom_point(aes(y=control, color="control"))
# Plot ratios between values
plot_ratios <- ggplot(results, aes(x=index, y=ratio)) +
geom_point()
# Arrange the two plots above each other
grid.arrange(plot_values, plot_ratios, ncol=1, nrow=2)
The big problem is that the legend on the right of the first plot makes it a different size. A minor problem is that I'd rather not show the x-axis name and tick marks on the top plot, to avoid clutter and make it clear that they share the same axis.
I've looked at this question and its answers:
Align plot areas in ggplot
Unfortunately, neither answer there works well for me. Faceting doesn't seem a good fit, since I want to have completely different y scales for my two graphs. Manipulating the dimensions returned by ggplot_gtable seems more promising, but I don't know how to get around the fact that the two graphs have a different number of cells. Naively copying that code doesn't seem to change the resulting graph dimensions for my case.
Here's another similar question:
The perils of aligning plots in ggplot
The question itself seems to suggest a good option, but rbind.gtable complains if the tables have different numbers of columns, which is the case here due to the legend. Perhaps there's a way to slot in an extra empty column in the second table? Or a way to suppress the legend in the first graph and then re-add it to the combined graph?
Here's a solution that doesn't require explicit use of grid graphics. It uses facets, and hides the legend entry for "ratio" (using a technique from https://stackoverflow.com/a/21802022).
library(reshape2)
results_long <- melt(results, id.vars="index")
results_long$facet <- ifelse(results_long$variable=="ratio", "ratio", "values")
results_long$facet <- factor(results_long$facet, levels=c("values", "ratio"))
ggplot(results_long, aes(x=index, y=value, colour=variable)) +
geom_point() +
facet_grid(facet ~ ., scales="free_y") +
scale_colour_manual(breaks=c("control","value"),
values=c("#1B9E77", "#D95F02", "#7570B3")) +
theme(legend.justification=c(0,1), legend.position=c(0,1)) +
guides(colour=guide_legend(title=NULL)) +
theme(axis.title.y = element_blank())
Try this:
library(ggplot2)
library(gtable)
library(gridExtra)
AlignPlots <- function(...) {
LegendWidth <- function(x) x$grobs[[8]]$grobs[[1]]$widths[[4]]
plots.grobs <- lapply(list(...), ggplotGrob)
max.widths <- do.call(unit.pmax, lapply(plots.grobs, "[[", "widths"))
plots.grobs.eq.widths <- lapply(plots.grobs, function(x) {
x$widths <- max.widths
x
})
legends.widths <- lapply(plots.grobs, LegendWidth)
max.legends.width <- do.call(max, legends.widths)
plots.grobs.eq.widths.aligned <- lapply(plots.grobs.eq.widths, function(x) {
if (is.gtable(x$grobs[[8]])) {
x$grobs[[8]] <- gtable_add_cols(x$grobs[[8]],
unit(abs(diff(c(LegendWidth(x),
max.legends.width))),
"mm"))
}
x
})
plots.grobs.eq.widths.aligned
}
df <- data.frame(x = c(1:5, 1:5),
y = c(1:5, seq.int(5,1)),
type = factor(c(rep_len("t1", 5), rep_len("t2", 5))))
p1.1 <- ggplot(diamonds, aes(clarity, fill = cut)) + geom_bar()
p1.2 <- ggplot(df, aes(x = x, y = y, colour = type)) + geom_line()
plots1 <- AlignPlots(p1.1, p1.2)
do.call(grid.arrange, plots1)
p2.1 <- ggplot(diamonds, aes(clarity, fill = cut)) + geom_bar()
p2.2 <- ggplot(df, aes(x = x, y = y)) + geom_line()
plots2 <- AlignPlots(p2.1, p2.2)
do.call(grid.arrange, plots2)
Produces this:
// Based on multiple baptiste's answers
Encouraged by baptiste's comment, here's what I did in the end:
library(ggplot2)
library(dplyr)
library(gridExtra)
# Prepare some sample data.
results <- data.frame(index=(1:20))
results$control <- 50 * results$index
results$value <- results$index * 50 + 2.5*results$index^2 - results$index^3 / 8
results$ratio <- results$value / results$control
# Plot ratios between values
plot_ratios <- ggplot(results, aes(x=index, y=ratio)) +
geom_point()
# Plot absolute values
remove_x_axis =
theme(
axis.ticks.x = element_blank(),
axis.text.x = element_blank(),
axis.title.x = element_blank())
plot_values <- ggplot(results, aes(x=index)) +
geom_point(aes(y=value, color="value")) +
geom_point(aes(y=control, color="control")) +
remove_x_axis
# Arrange the two plots above each other
grob_ratios <- ggplotGrob(plot_ratios)
grob_values <- ggplotGrob(plot_values)
legend_column <- 5
legend_width <- grob_values$widths[legend_column]
grob_ratios <- gtable_add_cols(grob_ratios, legend_width, legend_column-1)
grob_combined <- gtable:::rbind_gtable(grob_values, grob_ratios, "first")
grob_combined <- gtable_add_rows(
grob_combined,unit(-1.2,"cm"), pos=nrow(grob_values))
grid.draw(grob_combined)
(I later realised I didn't even need to extract the legend width, since the size="first" argument to rbind tells it just to have that one override the other.)
It feels a bit messy, but it is exactly the layout I was hoping for.
An alternative & quite easy solution is as follows:
# loading needed packages
library(ggplot2)
library(dplyr)
library(tidyr)
# Prepare some sample data
results <- data.frame(index=(1:20))
results$control <- 50 * results$index
results$value <- results$index * 50 + 2.5*results$index^2 - results$index^3 / 8
results$ratio <- results$value / results$control
# reshape into long format
long <- results %>%
gather(variable, value, -index) %>%
mutate(facet = ifelse(variable=="ratio", "ratio", "values"))
long$facet <- factor(long$facet, levels=c("values", "ratio"))
# create the plot & remove facet labels with theme() elements
ggplot(long, aes(x=index, y=value, colour=variable)) +
geom_point() +
facet_grid(facet ~ ., scales="free_y") +
scale_colour_manual(breaks=c("control","value"), values=c("green", "red", "blue")) +
theme(axis.title.y=element_blank(), strip.text=element_blank(), strip.background=element_blank())
which gives:

ggplot2-line plotting with TIME series and multi-spline

This question's theme is simple but drives me crazy:
1. how to use melt()
2. how to deal with multi-lines in single one image?
Here is my raw data:
a 4.17125 41.33875 29.674375 8.551875 5.5
b 4.101875 29.49875 50.191875 13.780625 4.90375
c 3.1575 29.621875 78.411875 25.174375 7.8012
Q1:
I've learn from this post Plotting two variables as lines using ggplot2 on the same graph to know how to draw the multi-lines for multi-variables, just like this:
The following codes can get the above plot. However, the x-axis is indeed time-series.
df <- read.delim("~/Desktop/df.b", header=F)
colnames(df)<-c("sample",0,15,30,60,120)
df2<-melt(df,id="sample")
ggplot(data = df2, aes(x=variable, y= value, group = sample, colour=sample)) + geom_line() + geom_point()
I wish it could treat 0 15 30 60 120 as real number to show the time series, rather than name_characteristics. Even having tried this, I failed.
row.names(df)<-df$sample
df<-df[,-1]
df<-as.matrix(df)
df2 <- data.frame(sample = factor(rep(row.names(df),each=5)), Time = factor(rep(c(0,15,30,60,120),3)),Values = c(df[1,],df[2,],df[3,]))
ggplot(data = df2, aes(x=Time, y= Values, group = sample, colour=sample))
+ geom_line()
+ geom_point()
Loooooooooking forward to your help.
Q2:
I've learnt that the following script can add the spline() function for single one line, what about I wish to apply spline() for all the three lines in single one image?
n <-10
d <- data.frame(x =1:n, y = rnorm(n))
ggplot(d,aes(x,y))+ geom_point()+geom_line(data=data.frame(spline(d, n=n*10)))
Your variable column is a factor (you can verify by calling str(df2)). Just convert it back to numeric:
df2$variable <- as.numeric(as.character(df2$variable))
For your other question, you might want to stick with using geom_smooth or stat_smooth, something like this:
p <- ggplot(data = df2, aes(x=variable, y= value, group = sample, colour=sample)) +
geom_line() +
geom_point()
library(splines)
p + geom_smooth(aes(group = sample),method = "lm",formula = y~bs(x),se = FALSE)
which gives me something like this:

Plotting two variables using ggplot2 - same x axis

I have two graphs with the same x axis - the range of x is 0-5 in both of them.
I would like to combine both of them to one graph and I didn't find a previous example.
Here is what I got:
c <- ggplot(survey, aes(often_post,often_privacy)) + stat_smooth(method="loess")
c <- ggplot(survey, aes(frequent_read,often_privacy)) + stat_smooth(method="loess")
How can I combine them?
The y axis is "often privacy" and in each graph the x axis is "often post" or "frequent read".
I thought I can combine them easily (somehow) because the range is 0-5 in both of them.
Many thanks!
Example code for Ben's solution.
#Sample data
survey <- data.frame(
often_post = runif(10, 0, 5),
frequent_read = 5 * rbeta(10, 1, 1),
often_privacy = sample(10, replace = TRUE)
)
#Reshape the data frame
survey2 <- melt(survey, measure.vars = c("often_post", "frequent_read"))
#Plot using colour as an aesthetic to distinguish lines
(p <- ggplot(survey2, aes(value, often_privacy, colour = variable)) +
geom_point() +
geom_smooth()
)
You can use + to combine other plots on the same ggplot object. For example, to plot points and smoothed lines for both pairs of columns:
ggplot(survey, aes(often_post,often_privacy)) +
geom_point() +
geom_smooth() +
geom_point(aes(frequent_read,often_privacy)) +
geom_smooth(aes(frequent_read,often_privacy))
Try this:
df <- data.frame(x=x_var, y=y1_var, type='y1')
df <- rbind(df, data.frame(x=x_var, y=y2_var, type='y2'))
ggplot(df, aes(x, y, group=type, col=type)) + geom_line()

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