YOU HAVE SPOKEN and we will go with ticks out, at least 54% of the time.

In a graph, should axis ticks face in or out?

— Leonard Kiefer (@lenkiefer) February 5, 2017

To celebrate, let’s make an animated gif where the axis expands over time. We’ll use data we used in our mortgage rate post.

Let’s start by loading the data and plotting a static graph (with ticks out of course).

####################
####  Load Data ####
####################
library(readxl)
library(tidyverse) 

## -- Attaching packages -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- tidyverse 1.2.1 --

## v ggplot2 2.2.1     v purrr   0.2.4
## v tibble  1.4.2     v dplyr   0.7.4
## v tidyr   0.8.0     v stringr 1.3.0
## v readr   1.1.1     v forcats 0.3.0

## -- Conflicts ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- tidyverse_conflicts() --
## x dplyr::filter() masks stats::filter()
## x dplyr::lag()    masks stats::lag()

library(data.table)

## Warning: package 'data.table' was built under R version 3.6.0

## 
## Attaching package: 'data.table'

## The following objects are masked from 'package:dplyr':
## 
##     between, first, last

## The following object is masked from 'package:purrr':
## 
##     transpose

library(extrafont)

## Registering fonts with R

#for mor on these data see http://lenkiefer.com/2016/12/08/10-ways-to-visualize-rates

dt<- read_excel('data/rates.xlsx',sheet= 'rates')
dt$date<-as.Date(dt$date, format="%m/%d/%Y")
dt<-data.table(dt) 
dt$year<-year(dt$date) # create year variable

###########################################
#######  Functions for better axis ########
###########################################

################################
# for use with continuous axis
################################
base_breaks_x <- function(x){
  b <- pretty(x)
  d <- data.frame(y=-Inf, yend=-Inf, x=min(b), xend=max(b))
  list(geom_segment(data=d, aes(x=x, y=y, xend=xend, yend=yend), inherit.aes=FALSE),
       scale_x_continuous(breaks=b))
}

################################
# for use with date axis
################################

base_breaks_x_date <- function(x,dd,dd.format="default"){
  #b <- pretty(x)
  b<- c(min(x),max(x))
  b2<- c(min(dd),max(dd))
  if (dd.format != "default") {b2<-as.character(b2,format=dd.format)}
  d <- data.frame(y=-Inf, yend=-Inf, x=min(x), xend=max(x))
  list(geom_segment(data=d, aes(x=x, y=y, xend=xend, yend=yend), 
                    inherit.aes=FALSE),
       scale_x_continuous(breaks=b,labels=b2))
}

################################
# for use on y axis
################################
base_breaks_y <- function(x){
  b <- pretty(x)
  d <- data.frame(x=-Inf, xend=-Inf, y=min(b), yend=max(b))
  list(geom_segment(data=d, aes(x=x, y=y, xend=xend, yend=yend), inherit.aes=FALSE),
       scale_y_continuous(breaks=b))
}


#####################
####  Make Graph ####
#####################


ggplot(data=dt, aes(x=as.numeric(date),y=rate30,label=rate30))+
  geom_line()+theme_bw()+
  #scale_x_date(date_breaks="1 month", date_labels="%b-%y")+
  #scale_y_continuous(limits=c(3,4.4),breaks=seq(3,4.4,.1))+
   labs(x="", y="",
       title="30-year Fixed Mortgage Rate (%)",
       subtitle="weekly average rates",
       caption="@lenkiefer Source: Freddie Mac Primary Mortgage Market Survey")+
  theme(plot.title=element_text(size=18),
        plot.caption=element_text(hjust=0))+
  theme(panel.border = element_blank(),
        panel.grid.major = element_blank(),
                text=element_text(family="Palatino Linotype"),
        panel.grid.minor = element_blank(),
                axis.ticks.length=unit(0.25,"cm")        ) + 
  ### Use our sweet axis functions:
  base_breaks_x_date(as.numeric(dt$date),dt$date) +
  base_breaks_y(dt$rate30)

library(tweenr)

myf<-function(dd,dmin=as.Date("2014-12-31"),
              #Variable subt contains annotations in the subtitle frame
              subt="Nothing",
              keepdots="No"){
  DT2<-copy(dt)
  #set max to last value
  DT2[date>dd,rate30:=dt[date==dd]$rate30]
  DT2[date>dd,date:=dd]
  #set min to first value
  DT2[date<=dmin,rate30:=dt[date==dmin]$rate30]
  DT2[date<=dmin,date:=dmin]
  DT2[,subt:=label_wrap_gen(100)(subt)]
  DT2$subt<-factor(DT2$subt)
  DT2$keepdots<-factor(keepdots)
  as.data.frame(DT2[, list(date,rate30,subt,keepdots)])}


tf <- tween_states(
  list(myf(as.Date("2016-11-03"),as.Date("2015-12-31"),subt="rates fell throughout most of 2016 up to the U.S. general election..."),
       myf(as.Date("2017-02-02"),as.Date("2015-12-31"),subt="...rising rapidly after the election...."),
       myf(as.Date("2017-02-02"),as.Date("2012-12-27"),subt="...having declined after the Taper Talk in 2013...."),
       myf(as.Date("2017-02-02"),as.Date("1971-04-02"),subt="...and after over 30 years of general decline."),
       myf(as.Date("2015-12-31"),as.Date("2012-12-27"),subt="...rates entered 2016 above 4%, but..."),myf(as.Date("2016-11-03"),as.Date("2015-12-31"),subt="rates fell throughout most of 2016 up to the U.S. general election...")
         ),tweenlength= 3, statelength=1, ease=rep('cubic-in-out',2),nframes=110)
tf<-data.table(tf)

oopt = ani.options(interval = 0.15)
saveGIF({for (i in 1:max(tf$.frame)) {
  dt3<-tf[.frame==i]
    g<-
      ggplot(data=dt3, aes(x=as.numeric(date),y=rate30,label=rate30))+
      geom_line()+theme_bw()+
  #scale_x_date(date_breaks="1 month", date_labels="%b-%y")+
  #scale_y_continuous(limits=c(3,4.4),breaks=seq(3,4.4,.1))+
   labs(x="", y="",
       title="30-year Fixed Mortgage Rate (%)",
        subtitle=tf[.frame==i,]$subt,
       caption="@lenkiefer Source: Freddie Mac Primary Mortgage Market Survey")+
  theme(plot.title=element_text(size=18),
        plot.caption=element_text(hjust=0))+
  theme(panel.border = element_blank(),
        panel.grid.major = element_blank(),
                text=element_text(family="Palatino Linotype"),
        panel.grid.minor = element_blank(),
        axis.ticks.length=unit(0.25,"cm")        ) + 
  ### Use our sweet axis functions:
  base_breaks_x_date(as.numeric(dt3$date),dt3$date) +
  base_breaks_y(dt3$rate30)
    
    print(g)
    ani.pause()
    print(i)
  }
},movie.name="rate_02_06_annotate.gif",ani.width = 500, ani.height = 350)

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