Monthly Archives: November 2015

Polar Circles

You cannot find peace by avoiding life (Virginia Woolf)

Combining polar coordinates, RColorBrewer palettes, ggplot2 and a simple trigonometric function to define the width of the tiles is easy to produce nice circular plots like these:

polar_flower4polar_flower2polar_flower1polar_flower3

Do you want to try? Here you have the code:

library(ggplot2)
library(dplyr)
library(RColorBrewer)
n=500
m=50
w=sapply(seq(from=-3.5*pi, to=3.5*pi, length.out=n), function(x) {abs(sin(x))})
x=c(1)
for (i in 2:n) {x[i]=x[i-1]+1/2*(w[i-1]+w[i])}
expand.grid(x=x, y=1:m) %>%
  mutate(w=rep(w, m))-> df
opt=theme(legend.position="none",
          panel.background = element_rect(fill="white"),
          panel.grid=element_blank(),
          axis.ticks=element_blank(),
          axis.title=element_blank(),
          axis.text=element_blank())
ggplot(df, aes(x=x,y=y))+geom_tile(aes(fill=x, width=w))+ 
  scale_fill_gradient(low=brewer.pal(9, "Greens")[1], high=brewer.pal(9, "Greens")[9])+
  coord_polar(start = runif(1, min = 0, max = 2*pi))+opt
ggplot(df, aes(x=x,y=y))+geom_tile(aes(fill=w, width=w))+ 
  scale_fill_gradient(low=brewer.pal(9, "Reds")[1], high=brewer.pal(9, "Reds")[9])+ 
  coord_polar(start = runif(1, min = 0, max = 2*pi))+opt
ggplot(df, aes(x=x,y=y))+geom_tile(aes(fill=y, width=w))+ 
  scale_fill_gradient(low=brewer.pal(9, "Purples")[1], high=brewer.pal(9, "Purples")[9])+ 
  coord_polar(start = runif(1, min = 0, max = 2*pi))+opt
ggplot(df, aes(x=x,y=y))+geom_tile(aes(fill=w*y, width=w))+ 
  scale_fill_gradient(low=brewer.pal(9, "Blues")[9], high=brewer.pal(9, "Blues")[1])+ 
  coord_polar(start = runif(1, min = 0, max = 2*pi))+opt

The Batman’s Ecosystem

If I weren’t crazy, I’d be insane! (Joker)

I present today a dynamical D3.js plot where I combine three things:

  • The Batman curve
  • A text mining analysis to obtain most common words from the Batman’s page at Wikipedia
  • A line plot using morris.js library of rCharts package where point labels are the words obtained in the previous step

This is my particular homage to one of the most amazing superheros ever, together with Daredevil. Since I am not allowed to post JavaScript nor embed objects in my WordPress.com blog, I can only show you an screenshot of the graph:

batman2
If you want to play with the graph, you can download it here. This is not the first time I write about Batman (see this), and maybe will not be the last one.

The code:

require(ggplot2)
require(dplyr)
require(rCharts)
library(rvest)
library(tm)
f1u <- function(x) {ifelse ((abs(x) >  3 & abs(x) <= 7), 3*sqrt(1-(x/7)^2), 0)}
f1d <- function(x) {ifelse ((abs(x) >= 4 & abs(x) <= 7), -3*sqrt(1-(x/7)^2), 0)}
f2u <- function(x) {ifelse ((abs(x) > 0.50 & abs(x) < 0.75),  3*abs(x)+0.75, 0)}
f2d <- function(x) {ifelse ((abs(x) > -4 & abs(x) < 4), abs(x/2)-(3*sqrt(33)-7)*x^2/112-3 + sqrt(1-(abs(abs(x)-2)-1)^2), 0)}
f3u <- function(x) {ifelse ((x > -0.5 & x < 0.5), 2.25, 0)}
f4u <- function(x) {ifelse ((abs(x) >  1 & abs(x) <= 3), 6 * sqrt(10)/7 + (1.5 - 0.5 * abs(x)) * sqrt(abs(abs(x)-1)/(abs(x)-1)) - 6 * sqrt(10) * sqrt(4-(abs(x)-1)^2)/14, 0)}
f5u <- function(x) {ifelse ((abs(x) >= 0.75 & abs(x) <= 1), 9-8*abs(x), 0)}
fu <- function (x) f1u(x)+f2u(x)+f3u(x)+f4u(x)+f5u(x)
fd <- function (x) f1d(x)+f2d(x)
batman <- function(r,x) {ifelse(r%%2==0, fu(x), fd(x))}
data.frame(x=seq(from=-7, to=7, by=0.125)) %>%
  mutate(y=batman(row_number(), x)) -> df
html("https://en.wikipedia.org/wiki/Batman") %>%
  html_nodes("#bodyContent")  %>%
  html_text() %>%
  VectorSource() %>%
  Corpus() %>%
  tm_map(tolower) %>%
  tm_map(removePunctuation) %>%
  tm_map(removeNumbers) %>%  
  tm_map(stripWhitespace) %>%
  tm_map(removeWords, c(stopwords(kind = "en"), "batman", "batmans")) %>%
  DocumentTermMatrix() %>%
  as.matrix() %>%
  colSums() %>%
  sort(decreasing=TRUE) %>%
  head(n=nrow(df)) %>%
  attr("names") -> df$word
m1=mPlot(x = "x",  y = "y",  data = df,  type = "Line")
m1$set(pointSize = 5,
       lineColors = c('black', 'black'),
       width = 900,
       height = 500,
       hoverCallback = "#! function(index, options, content)
                  { var row = options.data[index]
                  return '<b>' + row.word + '</b>'} !#",
       lineWidth = 2,
       grid=FALSE,
       axes=FALSE)
m1
m1$save('Batman.html', standalone = TRUE)