plotly.Rmd

---
title: "Plotly"
author: "Yao Yu"
date: "11/19/2019"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)

library(janitor)
library(plotly)
library(tidyverse)
```

```{r accumulate by function}

# This accumulate_by function can be found on the plotly documentation page for
# making animated graphics and is used to calculate animated frames:
# https://plot.ly/r/cumulative-animations/

accumulate_by <- function(dat, var) {
  var <- lazyeval::f_eval(var, dat)
  lvls <- plotly:::getLevels(var)
  dats <- lapply(seq_along(lvls), function(x) {
    cbind(dat[var %in% lvls[seq(1, x)], ], frame = lvls[[x]])
  })
  dplyr::bind_rows(dats)
}
```

```{r load in data}

# Reads in csv and cleans names

violence_capita <- read.csv("raw_data/violence_data_per_capita.csv") %>%
  clean_names()

# Cleans the data to fit the plotly and then cleans names again for the graphic

graphic_capita <- violence_capita %>%
  gather(key = "cities", value = "deaths", san_francisco_violent:st_louis_violent) %>%
  mutate(cities = ifelse(cities == "san_francisco_violent", "San Francisco", cities),
         cities = ifelse(cities == "oakland_violent", "Oakland", cities),
         cities = ifelse(cities == "baltimore_violent", "Baltimore", cities),
         cities = ifelse(cities == "chicago_violent", "Chicago", cities),
         cities = ifelse(cities == "st_louis_violent", "St. Louis", cities)) %>%
  accumulate_by(~year)

# Saves cleaned dataset to an RDS file for the Shiny App

saveRDS(object = graphic_capita, file = "RDS/graphic_violence_capita.RDS")
```

```{r plotly code}

# Creating the animated graphic, this code will be copied to the Shiny App.
# Tutorial can be found on the documentation page:
# https://plot.ly/r/cumulative-animations/

p <- plot_ly(
    data = graphic_capita,
    x = ~year, 
    y = ~deaths,
    color = ~cities,
    frame = ~frame,
    text = ~cities, 
    hoverinfo = "text",
    type = 'scatter',
    mode = 'lines'
  ) %>% 
  
  # layout() is similar to labs() in ggplot to add title, axis-labels, caption (annotation)
  
  layout(
    title = 'Number of Violent Crimes in Cities Per Year Per Capita',
    xaxis = list(
      title = "Year",
      zeroline = F
    ),
    yaxis = list(
      title = "Violent Crimes Per Capita",
      zeroline = F
    ),
    annotations = list(x = 1, y = -0.12, text = "Source: Census.gov, fbi.gov", 
      showarrow = F, xref='paper', yref='paper', 
      xanchor='right', yanchor='auto', xshift=0, yshift=0,
      font=list(size=15, color="black"))
 )
```