when I use ggplot2::ggplot() to create a map using a shapefile I have the problem that small features overlaped by bigger ones. Please note image of the Problem: ggplot overlays the small county by the bigger one.
Please use this shapefile as input data.
load("~/Germany_Bremen_LowerSax_NUTS1.Rdata") # Please use input data mentioned above
library(ggplot2)
plot(shp.nuts.test) # normal plot with visible borders.
shp.f <- fortify(shp.nuts.test)
Map <- ggplot(shp.f, aes(long, lat, group = group, fill = id))+
geom_polygon()
Map
Is there any possibility to change the plot order of the shapefile within ggplot?
Any help appreciated! Thanks!
There are a couple of options:
Reorder factors so that the lower levels plot on top of the higher ones.
Add another layer of the hidden group over the plot (shown below)
library(dplyr)
ggplot(shp.f, aes(long, lat, group = group, fill = id))+
geom_polygon()+
geom_polygon(aes(long,lat), data=filter(shp.f, group=='4.1'))
I personally prefer option 2, because it is a huge pain reordering factors and can easily result in unintended consequences. In addition, you could handle more layers on top. Note that the filter function requires the dplyr library (more on dplyr use).
Related
I have a dataset myData which contains x and y values for various Samples. I can create a line plot for a dataset which contains a few Samples with the following pseudocode, and it is a good way to represent this data:
myData <- data.frame(x = 290:450, X52241 = c(..., ..., ...), X75123 = c(..., ..., ...))
myData <- myData %>% gather(Sample, y, -x)
ggplot(myData, aes(x, y)) + geom_line(aes(color=Sample))
Which generates:
This turns into a Spaghetti Plot when I have a lot more Samples added, which makes the information hard to understand, so I want to represent the "hills" of each sample in another way. Preferably, I would like to represent the data as a series of stacked bars, one for each myData$Sample, with transparency inversely related to what is in myData$y. I've tried to represent that data in photoshop (badly) here:
Is there a way to do this? Creating faceted plots using facet_wrap() or facet_grid() doesn't give me what I want (far too many Samples). I would also be open to stacked ridgeline plots using ggridges, but I am not understanding how I would be able to convert absolute values to a stat(density) value needed to plot those.
Any suggestions?
Thanks to u/Joris for the helpful suggestion! Since, I did not find this question elsewhere, I'll go ahead and post the pretty simple solution to my question here for others to find.
Basically, I needed to apply the alpha aesthetic via aes(alpha=y, ...). In theory, I could apply this over any geom. I tried geom_col(), which worked, but the best solution was to use geom_segment(), since all my "bars" were going to be the same length. Also note that I had to "slice" up the segments in order to avoid the problem of overplotting similar to those found here, here, and here.
ggplot(myData, aes(x, Sample)) +
geom_segment(aes(x=x, xend=x-1, y=Sample, yend=Sample, alpha=y), color='blue3', size=14)
That gives us the nice gradient:
Since the max y values are not the same for both lines, if I wanted to "match" the intensity I normalized the data (myDataNorm) and could make the same plot. In my particular case, I kind of preferred bars that did not have a gradient, but which showed a hard edge for the maximum values of y. Here was one solution:
ggplot(myDataNorm, aes(x, Sample)) +
geom_segment(aes(x=x, xend=x-1, y=Sample, y=end=Sample, alpha=ifelse(y>0.9,1,0)) +
theme(legend.position='none')
Better, but I did not like the faint-colored areas that were left. The final code is what gave me something that perfectly captured what I was looking for. I simply moved the ifelse() statement to apply to the x aesthetic, so the parts of the segment drawn were only those with high enough y values. Note my data "starts" at x=290 here. Probably more elegant ways to combine those x and xend terms, but whatever:
ggplot(myDataNorm, aes(x, Sample)) +
geom_segment(aes(
x=ifelse(y>0.9,x,290), xend=ifelse(y>0.9,x-1,290),
y=Sample, yend=Sample), color='blue3', size=14) +
xlim(290,400) # needed to show entire scale
Suppose we have a set of commodities (apples, bananas, potatoes etc) distributed over different continents. We visualize their distribution on continents via faceted barcharts in ggplot2 package, and these commodities (called in what follows "stuff" field) act as factors to be displayed on x axis. Each continent has its own set of stuff, as shown in the data, although certain commodities can be common (bananas) on two or more continents. Here is the data example in short format. Fields "medium" and "giant" additionally subdivide the market separating out things into medium and big sizes (to be plotted with different colours).
data<-read.csv(text="continent,stuff,average,giant
North America,apples,20,30
North America,bananas,25,32
Europe,bananas,15,25
Europe,potatoes,10,20
Europe,mosquitoes,13,17
Asia,snakes,26,35
Asia,snails,7,15
Asia,pandas,10,20")
First we reduce the data to long format, and next plot it via geom_col() and faceting technique:
library(dplyr)
library(tidyr)
library(ggplot2)
data.tidied<-data %>%
gather(key=size, value=val,-continent,-stuff)
ggplot(data.tidied,aes(x=stuff,y=val,fill=size))+
geom_col(position="dodge")+
facet_grid(~continent)+coord_flip()
All factors in the stuff are aligned across all continents, although most of them are not needed, so there are many gaps. But we don't need any snails in North America and Europe, it is natural to have this field only for the Asia facet and so on. (To make things clearer, you may think of apples/bananas/potatoes as some geographical localities, unique for a continent: we do not have any California in Europe). So: how to display this situation using nevertheless faceting technique of ggplot (or any alternative)? That is: how to draw a unique set of factors for each facet?
You can use facet_wrap instead of facet_grid and specify scales = "free_y" (has to be free_y as you flipped the axes). But it makes the charts look a little odd, in my opinion.
data %>%
gather(size, val, -continent, -stuff) %>%
ggplot(aes(stuff, val)) +
geom_col(aes(fill = size), position = "dodge") +
facet_wrap(~continent, scales = "free_y") +
coord_flip()
I am trying to build from a question similar to mine (and from which I borrowed the self-contained example and title inspiration). I am trying to apply transparency individually to each line of a ggparcoord or somehow add two layers of ggparcoord on top of the other. The detailed description of the problem and format of data I have for the solution to work is provided below.
I have a dataset with thousand of lines, lets call it x.
library(GGally)
x = data.frame(a=runif(100,0,1),b=runif(100,0,1),c=runif(100,0,1),d=runif(100,0,1))
After clustering this data I also get a set of 5 lines, let's call this dataset y.
y = data.frame(a=runif(5,0,1),b=runif(5,0,1),c=runif(5,0,1),d=runif(5,0,1))
In order to see the centroids y overlaying x I use the following code. First I add y to x such that the 5 rows are on the bottom of the final dataframe. This ensures ggparcoord will put them last and therefore stay on top of all the data:
df <- rbind(x,y)
Next I create a new column for df, following the question advice I referred such that I can color differently the centroids and therefore can tell it apart from the data:
df$cluster = "data"
df$cluster[(nrow(df)-4):(nrow(df))] <- "centroids"
Finally I plot it:
p <- ggparcoord(df, columns=1:4, groupColumn=5, scale="globalminmax", alphaLines = 0.99) + xlab("Sample") + ylab("log(Count)")
p + scale_colour_manual(values = c("data" = "grey","centroids" = "#94003C"))
The problem I am stuck with is from this stage and onwards. On my original data, plotting solely x doesn't lead to much insight since it is a heavy load of lines (on this data this is equivalent to using ggparcoord above on x instead of df:
By reducing alphaLines considerably (0.05), I can naturally see some clusters due to the overlapping of the lines (this is again running ggparcoord on x reducing alphaLines):
It makes more sense to observe the centroids added to df on top of the second plot, not the first.
However, since everything it is on a single dataframe, applying such a high value for alphaLine makes the centroid lines disappear. My only option is then to use ggparcoord (as provided above) on df without decreasing the alphaValue:
My goal is to have the red lines (centroid lines) on top of the second figure with very low alpha. There are two ways I thought so far but couldn't get it working:
(1) Is there any way to create a column on the dataframe, similar to what is done for the color, such that I can specify the alpha value for each line?
(2) I originally attempted to create two different ggparcoords and "sum them up" hoping to overlay but an error was raised.
The question may contain too much detail, but I thought this could motivate better the applicability of the answer to serve the interest of other readers.
The answer I am looking for would use the provided data variables on the current format and generate the plot I am looking for. Better ways to reconstruct the data is also welcomed, but using the current structure is preferred.
In this case I think it easier to just use ggplot, and build the graph yourself. We make slight adjustments to how the data is represented (we put it in long format), and then we make the parallel coordinates plot. We can now map any attribute to cluster that you like.
library(dplyr)
library(tidyr)
# I start the same as you
x <- data.frame(a=runif(100,0,1),b=runif(100,0,1),c=runif(100,0,1),d=runif(100,0,1))
y <- data.frame(a=runif(5,0,1),b=runif(5,0,1),c=runif(5,0,1),d=runif(5,0,1))
# I find this an easier way to combine the two data.frames, and have an id column
df <- bind_rows(data = x, centroids = y, .id = 'cluster')
# We need to add id's, so we know which points to connect with a line
df$id <- 1:nrow(df)
# Put the data into long format
df2 <- gather(df, 'column', 'value', a:d)
# And plot:
ggplot(df2, aes(column, value, alpha = cluster, color = cluster, group = id)) +
geom_line() +
scale_colour_manual(values = c("data" = "grey", "centroids" = "#94003C")) +
scale_alpha_manual(values = c("data" = 0.2, "centroids" = 1)) +
theme_minimal()
I am trying to plot two Cumulative Frequency curves in ggplot, and shade the cross over at a certain cut off. I haven't been using ggplot for long, so I was hoping someone might be able to help me with this one.
The plot without filled regions, looks like this...
Which I have created using the following code...
library(ggplot2) # required
north <- rnorm(3060, mean=277,sd=3.01) # to create synthetic data
south <- rnorm(3060, mean=278, sd=3.26) # in place of my real data.
#placing in dataframe
df_temp <- data.frame(temp=c(north,south),
region=c(rep("north",length=3060),rep("south",length=3060)))
#manipulating into cdf, as I've seen in other examples
temp.regions <- ddply(df_temp, .(region), summarize,
temp = unique(temp),
ecdf = ecdf(temp)(unique(temp)))
# feeding into ggplot.
ggplot(temp.regions,aes(x=temp, y=ecdf, color = region)) +
geom_line(aes(x=temp,color=region))+
scale_colour_manual(values = c("blue","red"))
What I would then like, would be to shade both curves for temperatures below 0.2 on the y axis. Ideally I'd like to see the blue one shaded in blue, and the red one shaded in red. Then, where they cross over in purple.
However, the closest I have managed is as follows... ]
Which I have achieved using the following additions to my code.
# creating a dataframe with just the temperatures for below 0.2
# to try and aid control when plotting
temp.below <- temp.regions[which(temp.regions$ecdf<0.2),]
# plotting routine again.
ggplot(temp.regions, aes(x=temp, y=ecdf, color = region)) +
geom_line(aes(x=temp,color=region))+
scale_colour_manual(values = c("blue","red"))+
# with additional line for shading.
geom_ribbon(data=temp.below,
aes(x=temp,ymin=0,ymax=0.2), alpha=0.5)
I've seen a few examples of people shading for a normal distribution density plot, which is where I have adapted my code from. But for some reason my boxes don't seem to want anything to do with the temperature curve.
Please help! I'm sure it's quite simple, I'm just really lost and have tried a few, producing less convincing results than these.
Thank you so much for taking a look.
PROBLEM SOLVED THANKS TO HELP BELOW...
running suggested code from below
geom_ribbon(aes(ymin=0,ymax=ecdf, fill=region), alpha=0.5)
gives...
which is so very almost the solution I'm after, but with one final addition... like so
#geom_ribbon(aes(ymin=0,ymax=ecdf, fill=region), alpha=0.5)
geom_ribbon(data=temp.below, aes(ymin=0,ymax=ecdf, fill=region), alpha=0.5)
I get what I'm after...
The reason I set the data again is so that it only fills the lowest 20% of the two regions.
Thank you so much for the help :-)
Looks like you're thinking about it in the right way.
With geom_ribbon i dont think you need to set data to anything else. Just set aes(ymin = 0, ymax = ecdf, fill = region). I think that should do it.
I am making heat maps from correlations. I have two columns that represent ID's and a third column that gives the correlation between those two datapoints. I am struggling to get qplot to keep the order of my data in the file. Link to data:
https://www.dropbox.com/s/3l9p1od5vjt0p4d/SNPS.txt?n=7399684
Here is the code I am using to make the plot:
test <- qplot(x=x, y=y, data=PCIT, fill = col1, geom = "tile")
I have tried several order options but they don't seem to do the trick? Ideas?
Thanks and Happy Holidays
You need to set the levels of the factors x and y to be in the order you want them (as they come in from the file). Try
PCIT$x <- factor(PCIT$x, levels=unique(as.character(PCIT$x)))
and similarly with y.