WebGLHeatmap-small.Rmd

---
title: "WebGLHeatmap-small"
output:
  html_notebook: default
---

## Data preparation

```{r data loading}
library(tibble)
library(dplyr)

paris <- list()
paris$min <- list(Long = 2.199669, Lat = 48.806185)
paris$max <- list(Long = 2.481194, Lat = 48.899258)
paris$mean <- list(Long = mean(c(paris$min$Long, paris$max$Long)),
                   Lat = mean(c(paris$min$Lat, paris$max$Lat)))
paris$sd <- list(Long = (paris$max$Long - paris$min$Long) / 2,
                 Lat = (paris$max$Lat - paris$min$Lat) / 2)
```

```{r sample creation}
set.seed(1000)

bigSample <- data_frame(Long = rnorm(n = 500E3, mean = paris$mean$Long, sd = paris$sd$Long),
                                 Lat = rnorm(n = 500E3, mean = paris$mean$Lat, sd = paris$sd$Lat))

mediumSample <- bigSample %>%
  sample_n(size =  100E3)

smallSample <- bigSample %>%
  sample_n(size =  10E3)
```

## Package preparation

```{r remove packages, warning = FALSE, eval=FALSE}
  remove.packages("leaflet")
  remove.packages("leaflet.extras")
```

```{r install packages,  eval=FALSE}
devtools::install_github('rstudio/leaflet')
devtools::install_github('bhaskarvk/leaflet.extras')
```

## Display Heatmap

```{r show heatmap}
library(leaflet)
library(leaflet.extras)
    leaflet(smallSample) %>%
      addProviderTiles("CartoDB.DarkMatter") %>%
      addWebGLHeatmap(lng=~Long,
                      lat=~Lat,
                      size = 5,
                      units = "px")
```