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While running for a couple of years now (since 2004) I wanted to see if there is some progress in speed and distance. I didn’t log much in the beginning, no notebook or anything like that, but around 2010 I purchased my first GPS watch. This enables automatic logging! Anyway, this is the result of 10 years of running:

Below code demonstates how this is created. It creates an image for every year. These files are later combined in an animated gif. There are different ways to achieve this, without creating and saving the seperate images. Perhaps I’ll write something about that in the future.

Graphs are created using ggplot, the MASS library is required to create the polygones. Sport_df.Rda contain all data and is created with another script which gets data from Strava and converts it to the data frame which I use here.

In a for...next loop a data frame is created for every year with distance in column x and pace in column y. this is reused every iteration. With the data in a stuctured in the way we like is we can now plot it using ggplot. 2D density lines will be added using stat_density2d from the MASS package.

Saving the plot as PNG with the prefix scat_den_run to be used later to filter these files from a directory with multiple plots.

library(ggplot2)
library(MASS)

jaar <- c(2011:2020)
for(i in jaar){
df_run <- data.frame("x"= Sport$dist[Sport$type=="Run" & Sport$year==i], "y"= Sport$pace[Sport$type=="Run" & Sport$year==i])

Run <- ggplot(data=df_run,aes(x,y)) +
stat_density2d(aes(fill=..level..,alpha=..level..), geom="polygon",colour="black") +
scale_fill_continuous(low="green",high="red") +
scale_y_reverse() +
geom_point() +
xlim(1,45) +
ylim(4,7) +
labs(title="Running pace versus distance", subtitle = i)

# Print graphs
filename_run <- paste("scat_den_run",i,".png", sep="")

png(filename=filename_run, width=1000, height=400, bg="black", type="cairo")
print(run)
dev.off()
}

Now all images have been created and placed in the directory. We only have to combine them into an animated gif using the fabulous magick package.

library(purrr)
library(magick)

files <- list.files(path = ".", pattern = c("scat_den_run",".png"))
#get all images in a list
image_write(animation, path="./animation_run.gif")