plot mantel.rtest with ggplot2 - r

I am performing a mantel test using the function mantel.rtest from ade4 on two Euclidean distance matrices to get the correlation between them. Since I would like to show the resulting plot for different tests, I would like to know if it would be possible to plot the mantel result using ggplot2 instead of the basic function plot.
first, of all I have tried to convert r1 into data.frame but I get this error:
r2 <- as.data.frame(r1)
Error in as.data.frame.default(r1) :
cannot coerce class ‘c("mantelrtest", "randtest", "lightrandtest")’ to a data.fr
I am adding a reproducible example:
data(yanomama)
gen <- quasieuclid(as.dist(yanomama$gen))
geo <- quasieuclid(as.dist(yanomama$geo))
plot(r1 <- mantel.rtest(geo,gen), main = "Mantel's test")
r1
Thanks a lot!

The following function will draw a ggplot for your mantelrtest object:
ggplot_mantel <- function(mant, fill = "gray50") {
df <- data.frame(x = mant$plot$hist$mids,
y = mant$plot$hist$counts)
ggplot(df, aes(x, y)) +
geom_col(orientation = "x",
width = diff(mant$plot$hist$breaks)[1],
fill = fill, color = "gray30") +
labs(x = mant$plot$hist$xname, y = "Frequency") +
scale_x_continuous(limits = mant$plot$xlim) +
geom_segment(aes(x = mant$obs, xend = mant$obs, y = 0,
yend = 0.75 * max(y))) +
geom_point(aes(x = mant$obs, y = 0.75 * max(y)), size = 5,
shape = 18)
}
So, using your own example:
plot(r1)
ggplot_mantel(r1)

Related

Add an additional X axis to the plot and some lines/annotations to show the percentage of data under it

I was trying to recreate this plot:
using the following code -
library(tidyverse)
set.seed(0); r <- rnorm(10000);
df <- as.data.frame(r)
avg <- round(mean(r),2)
SD <- round(sd(r),2)
x.scale <- seq(from = avg - 3*SD, to = avg + 3*SD, by = SD)
x.lab <- c("-3SD", "-2SD", "-1SD", "Mean", "1SD", "2SD", "3SD")
df %>% ggplot(aes(r)) +
geom_histogram(aes(y=..density..), bins = 20,
colour="black", fill="lightblue") +
geom_density(alpha=.2, fill="darkblue") +
scale_x_continuous(breaks = x.scale, labels = x.lab) +
labs(x = "")
Using the code I plotted this:
,
but this isn't near to the plot that I am trying to create. How do I make an additional axis with the X axis? How do I add the lines to automatically show the percentage of observations? Is there any way, that I can create the plot as nearly identical as possible using ggplot2?
Welcome to SO. Excellent first question!
It's actually quite tricky. You'd need to create a second plot (the second x axis) but it's not the most straight forward to align both perfectly.
I will be using Z.lin's amazing modification of the cowplot package.
I am not using the reprex package, because I think I'd need to define every single function (and I don't know how to use trace within reprex.)
library(tidyverse)
library(cowplot)
set.seed(0); r <- rnorm(10000);
foodf <- as.data.frame(r)
avg <- round(mean(r),2)
SD <- round(sd(r),2)
x.scale <- round(seq(from = avg - 3*SD, to = avg + 3*SD, by = SD), 1)
x.lab <- c("-3SD", "-2SD", "-1SD", "Mean", "1SD", "2SD", "3SD")
x2lab <- -3:3
# calculate the density manually
dens_r <- density(r)
# for each x value, calculate the closest x value in the density object and get the respective y values
y_dens <- dens_r$y[sapply(x.scale, function(x) which.min(abs(dens_r$x - x)))]
# added annotation for segments and labels.
# Arrow segments can be added in a similar way.
p1 <-
ggplot(foodf, aes(r)) +
geom_histogram(aes(y=..density..), bins = 20,
colour="black", fill="lightblue") +
geom_density(alpha=.2, fill="darkblue") +
scale_x_continuous(breaks = x.scale, labels = x.lab) +
labs(x = NULL) +# use NULL here
annotate(geom = "segment", x = x.scale, xend = x.scale,
yend = 1.1 * max(dens_r$y), y = y_dens, lty = 2 ) +
annotate(geom = "text", label = x.lab,
x = x.scale, y = 1.2 * max(dens_r$y))
p2 <-
ggplot(foodf, aes(r)) +
scale_x_continuous(breaks = x.scale, labels = x2lab) +
labs(x = NULL) +
theme_classic() +
theme(axis.line.y = element_blank())
# This is with the modified plot_grid() / align_plot() function!!!
plot_grid(p1, p2, ncol = 1, align = "v", rel_heights = c(1, 0.1))

How can I add annotation in ggplotly animation?

I am creating animated plotly graph for my assignment in r, where I am comparing several models with various number of observations. I would like to add annotation showing what is the RMSE of the current model - this means I would like to have text that changes together with slider. Is there any easy way how to do that?
Here is my dataset stored on GitHub. There already is created variable with RMSE: data
The base ggplot graphic is as follows:
library(tidyverse)
library(plotly)
p <- ggplot(values_predictions, aes(x = x)) +
geom_line(aes(y = preds_BLR, frame = n, colour = "BLR")) +
geom_line(aes(y = preds_RLS, frame = n, colour = "RLS")) +
geom_point(aes(x = x, y = target, frame = n, colour = "target"), alpha = 0.3) +
geom_line(aes(x = x, y = sin(2 * pi * x), colour = "sin(2*pi*x)"), alpha = 0.3) +
ggtitle("Comparison of performance) +
labs(y = "predictions and targets", colour = "colours")
This is converted to plotly, and I have added an animation to the Plotly graph:
plot <- ggplotly(p) %>%
animation_opts(easing = "linear",redraw = FALSE)
plot
Thanks!
You can add annotations to a ggplot graph using the annotate function: http://ggplot2.tidyverse.org/reference/annotate.html
df <- data.frame(x = rnorm(100, mean = 10), y = rnorm(100, mean = 10))
# Build model
fit <- lm(x ~ y, data = df)
# function finds RMSE
RMSE <- function(error) { sqrt(mean(error^2)) }
library(ggplot2)
ggplot(df, aes(x, y)) +
geom_point() +
annotate("text", x = Inf, y = Inf, hjust = 1.1, vjust = 2,
label = paste("RMSE", RMSE(fit$residuals)) )
There seems to be a bit of a problem converting between ggplot and plotly. However this workaround here shows a workaround which can be used:
ggplotly(plot) %>%
layout(annotations = list(x = 12, y = 13, text = paste("RMSE",
RMSE(fit$residuals)), showarrow = F))
Here's an example of adding data dependent text using the built in iris dataset with correlation as text to ggplotly.
library(plotly)
library(ggplot2)
library(dplyr)
mydata = iris %>% rename(variable1=Sepal.Length, variable2= Sepal.Width)
shift_right = 0.1 # number from 0-1 where higher = more right
shift_down = 0.02 # number from 0-1 where higher = more down
p = ggplot(mydata, aes(variable1,variable2))+
annotate(geom = "text",
label = paste0("Cor = ",as.character(round(cor.test(mydata$variable1,mydata$variable2)$estimate,2))),
x = min(mydata$variable1)+abs(shift_right*(min(mydata$variable1)-max(mydata$variable1))),
y = max(mydata$variable2)-abs(shift_down*(min(mydata$variable2)-max(mydata$variable2))), size=4)+
geom_point()
ggplotly(p) %>% style(hoverinfo = "none", traces = 1) # remove hover on text

r scatter plot with error bars in both directions

How can I create a scatter plot with error bars in two directions? Usually the error bars are in the vertical direction (i.e. the uncertainty in the y value). However my data has uncertainty in the x value as well
X ErrX Y ErrY
1.0 0.1 3.0 0.2
1.5 0.3 4.2 0.1
etc
Using ggplot2, this is easy. You have complete control over the length of all four "sides" of the errorbars. With geom_errorbar() you set the y-errors, and geom_errobarh() (the h is for horizontal) you set the x-errors.
#toy data
df <- data.frame(X = rnorm(4), errX = rnorm(4)*0.1, Y = rnorm(4), errY = rnorm(4)*0.2)
#load ggplot2
require(ggplot2)
#make graph
ggplot(data = df, aes(x = X, y = Y)) + geom_point() + #main graph
geom_errorbar(aes(ymin = Y-errY, ymax = Y+errY)) +
geom_errorbarh(aes(xmin = X-errX, xmax = X+errX))
You have separate control for the color of each bar, the linewidth, etc by setting parameters inside geom_errorbar(). See the help and Google for details. For example, you can control the width of the "caps" or eliminate them entirely with the width parameter. Compare the graph above to this one for an example of removing them:
ggplot(data = df, aes(x = X, y = Y)) + geom_point() +
geom_errorbar(aes(ymin = Y-errY, ymax = Y+errY), width = 0) +
geom_errorbarh(aes(xmin = X-errX, xmax = X+errX), height = 0)
As an alternative (using Curt F. 's "df"):
rangeX = range(c(df$X + df$errX, df$X - df$errX))
rangeY = range(c(df$Y + df$errY, df$Y - df$errY))
plot(df$X, df$Y, xlim = rangeX, ylim = rangeY)
segments(df$X, df$Y - df$errY, df$X, df$Y + df$errY)
segments(df$X - df$errX, df$Y, df$X + df$errX, df$Y)
Using error.crosses from my psych package + the toy data from Curt:
df1 <- data.frame(mean=df$X,sd=df$errX)
df2 <- data.frame(mean=df$Y,sd=df$errY)
error.crosses(df1,df2,sd=TRUE)
See the help page for error.crosses for some more complicated examples.

inheritance of aesthetics in ggplot2 0.9.3 & the behavior of annotation_custom

Following up on a recent question of mine, this one is a bit different and illustrates the problem more fully using simpler examples. Below are two data sets and three functions. The first one draws some points and a circle as expected:
library("ggplot2")
library("grid")
td1 <- data.frame(x = rnorm(10), y = rnorm(10))
tf1 <- function(df) { # works as expected
p <- ggplot(aes(x = x, y = y), data = df)
p <- p + geom_point(color = "red")
p <- p + annotation_custom(circleGrob())
print(p)
}
tf1(td1)
This next one seems to ask for the exact sample plot but the code is slightly different. It does not give an error but does not draw the circle:
tf2 <- function(df) { # circle isn't draw, but no error either
p <- ggplot()
p <- p + geom_point(data = df, aes(x = x, y = y), color = "red")
p <- p + annotation_custom(circleGrob())
print(p)
}
tf2(td1)
Finally, this one involves a more complex aesthetic and gives an empty layer when you try to create the circle:
td3 <- data.frame(r = c(rnorm(5, 5, 1.5), rnorm(5, 8, 2)),
f1 = c(rep("L", 5), rep("H", 5)), f2 = rep(c("A", "B"), 5))
tf3 <- function(df) {
p <- ggplot()
p <- p + geom_point(data = df,
aes(x = f1, y = r, color = f2, group = f2))
# p <- p + annotation_custom(circleGrob()) # comment out and it works
print(p)
}
tf3(td3)
Now, I suspect the problem here is not the code but my failure to grasp the inner workings of ggplot2. I could sure use an explanation of why the circle is not drawn in the 2nd case and why the layer is empty in the third case. I looked at the code for annotation_custom and it has a hard-wired inherit.aes = TRUE which I think is the problem. I don't see why this function needs any aesthetic at all (see the docs on it). I did try several ways to override it and set inherit.aes = FALSE but I was unable to fully penetrate the namespace and make it stick. I tried to example the objects created by ggplot2 but these proto objects are nested very deeply and hard to decipher.
To answer this :
"I don't see why this function needs any aesthetic at all".
In fact annotation_custom need x and y aes to scale its grob, and to use after the native units.
Basically it did this :
x_rng <- range(df$x, na.rm = TRUE) ## ranges of x :aes x
y_rng <- range(df$y, na.rm = TRUE) ## ranges of y :aes y
vp <- viewport(x = mean(x_rng), y = mean(y_rng), ## create a viewport
width = diff(x_rng), height = diff(y_rng),
just = c("center","center"))
dd <- editGrob(grod =circleGrob(), vp = vp) ##plot the grob in this vp
To illustrate this I add a grob to a dummy plot used as a scale for my grob. The first is a big scale and the second is a small one.
base.big <- ggplot(aes(x = x1, y = y1), data = data.frame(x1=1:100,y1=1:100))
base.small <- ggplot(aes(x = x1, y = y1), data = data.frame(x1=1:20,y1=1:1))
I define my grob, see I use the native scales for xmin,xmax,ymin,ymax
annot <- annotation_custom(grob = circleGrob(), xmin = 0,
xmax = 20,
ymin = 0,
ymax = 1)
Now see the scales difference(small point / big circle) between (base.big +annot) and (base.small + annot).
library(gridExtra)
grid.arrange(base.big+annot,
base.small+annot)

Non-linear color distribution over the range of values in a geom_raster

I'm faced with the following problem: a few extreme values are dominating the colorscale of my geom_raster plot. An example is probably more clear (note that this example only works with a recent ggplot2 version, I use 0.9.2.1):
library(ggplot2)
library(reshape)
theme_set(theme_bw())
m_small_sd = melt(matrix(rnorm(10000), 100, 100))
m_big_sd = melt(matrix(rnorm(100, sd = 10), 10, 10))
new_xy = m_small_sd[sample(nrow(m_small_sd), nrow(m_big_sd)), c("X1","X2")]
m_big_sd[c("X1","X2")] = new_xy
m = data.frame(rbind(m_small_sd, m_big_sd))
names(m) = c("x", "y", "fill")
ggplot(m, aes_auto(m)) + geom_raster() + scale_fill_gradient2()
Right now I solve this by setting the values over a certain quantile equal to that quantile:
qn = quantile(m$fill, c(0.01, 0.99), na.rm = TRUE)
m = within(m, { fill = ifelse(fill < qn[1], qn[1], fill)
fill = ifelse(fill > qn[2], qn[2], fill)})
This does not really feel like an optimal solution. What I would like to do is have a non-linear mapping of colors to the range of values, i.e. more colors present in the area with more observations. In spplot I could use classIntervals from the classInt package to calculate the appropriate class boundaries:
library(sp)
library(classInt)
gridded(m) = ~x+y
col = c("#EDF8B1", "#C7E9B4", "#7FCDBB", "#41B6C4",
"#1D91C0", "#225EA8", "#0C2C84", "#5A005A")
at = classIntervals(m$fill, n = length(col) + 1)$brks
spplot(m, at = at, col.regions = col)
To my knowledge it is not possible to hardcode this mapping of colors to class intervals like I can in spplot. I could transform the fill axis, but as there are negative values in the fill variable that will not work.
So my question is: are there any solutions to this problem using ggplot2?
Seems that ggplot (0.9.2.1) and scales (0.2.2) bring all you need (for your original m):
library(scales)
qn = quantile(m$fill, c(0.01, 0.99), na.rm = TRUE)
qn01 <- rescale(c(qn, range(m$fill)))
ggplot(m, aes(x = x, y = y, fill = fill)) +
geom_raster() +
scale_fill_gradientn (
colours = colorRampPalette(c("darkblue", "white", "darkred"))(20),
values = c(0, seq(qn01[1], qn01[2], length.out = 18), 1)) +
theme(legend.key.height = unit (4.5, "lines"))

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