11.2 Mini Plots

11.2.1 Goal

Plot a seasonal month plot as described in Hyndman and Athanasopoulos (2014, chapter 2.5):

Figure 11.4: Seasonal Plot with mini Time Plots over 10 Years

Here the seasonal patterns for each season are collected together in seprate mini time plots.

11.2.2 Data Basis

Figure 11.5: Raw Data for Seasonal Miniplots

11.2.3 Solution

Create a new script, copy/paste the following code and run it:

library(forecast)
library(dplyr)
library(plotly)
library(htmlwidgets)
library(ggthemes)
library(viridis)
library(lubridate)

# load csv file
df <- read.csv2("https://github.com/hslu-ige-laes/edar/raw/master/sampleData/flatHeatAndHotWater.csv",
                stringsAsFactors=FALSE)

# filter flat
df <- df %>% select(timestamp, Adr02_energyHeat)

colnames(df) <- c("timestamp", "meterValue")

# calculate consumption value per month
# pay attention, the value of 2010-02-01 00:00:00 represents the meter reading on february first,
# so the consumption for february first is value(march) - value(february)!
df <- df %>% dplyr::mutate(value = lead(meterValue) - meterValue)

# remove counter value column and calculate consumption per day instead of month
df <- df %>% 
  select(-meterValue) %>% 
  mutate(value = value /lubridate::days_in_month(timestamp))

# value correction (outlier because of commissioning)
df[1,2] <- 19

# create time series object for ggmonthplot function
df.ts <- ts(df[-1], frequency = 12, start = min(year(df$timestamp)))

# create x/y plot

numYears = length(unique(year(df$timestamp)))

plot <- ggmonthplot(df.ts,
                    col = viridis(numYears),
                    main = "Seasonal Miniplots over 10 years\n",
                    ylab = "Average Daily Energy Consumption per Month \n(kWh/day)\n",
                    xlab = "Month\n "
                    )

# change theme (optional)
plot <- plot + ggthemes::theme_economist()

# make plot interactive (optional)
plotly <- plotly::ggplotly(plot)

# show plot
plotly

# save static plot as png
ggsave("images/plotSeasonalMiniplots.png", plot)

# save interactive plot as html
library(htmlwidgets)
htmlwidgets::saveWidget(plotly, "plotlySeasonalMiniplots.html")

11.2.4 Discussion

• This type of seasonal plot shows the mean value of each month and therefore emphasises on the monthly comparison

• It revelas as well the mean seasonal pattern with the blue lines