Creating a Seasonal Box Plot in R and MATLAB: A Comparative Analysis.

Seasonal Box Plot in R and MATLAB

In this article, we will explore how to create a seasonal box plot using R and MATLAB. The box plot is a graphical representation that displays the distribution of data based on quartiles. We will discuss the concept of seasonal plots and how to implement them in both programming languages.

Seasonal Plots Overview

Seasonal plots are used to display the distribution of data over time, typically by grouping the data into different seasons (e.g., winter, spring, summer, fall). This type of plot is useful for identifying patterns or trends in the data that may be influenced by seasonal factors. In this article, we will focus on creating a seasonal box plot, which combines the features of both box plots and line graphs to display the distribution of data.

Creating a Seasonal Box Plot in R

R provides several libraries and functions to create a seasonal box plot. One popular approach is to use the tidyverse package, which includes dplyr, tidyr, and ggplot2. Here’s an example code that demonstrates how to create a seasonal box plot using R:

# Set the seed for reproducibility
set.seed(123)

library(tidyverse)
library(lubridate)

# Create example data frame
dt <- data_frame(DATE = seq(ymd("1980-01-01"), ymd("1989-12-31"), by = 1)) %>%
  mutate(obs1 = rnorm(nrow(.), mean = 0, sd = 1),
         obs2 = rnorm(nrow(.), mean = 1, sd = 2),
         obs3 = rnorm(nrow(.), mean = 2, sd = 3))

# Convert data frame from wide format to long format
dt2 <- dt %>% 
  gather(Observation, Value, -DATE) %>%
  mutate(Observation = str_replace(Observation, "obs", "")) %>%
  mutate(DATE = ymd(DATE)) %>%
  mutate(Month = month(DATE)) %>%
  mutate(Season = case_when(
    Month %in% c(12, 1, 2)      ~ "winter",
    Month %in% c(3, 4, 5)       ~ "spring",
    Month %in% c(6, 7, 8)       ~ "summer",
    Month %in% c(9, 10, 11)     ~ "fall",
    TRUE                        ~ NA_character_
  ))

# Create a boxplot using ggplot2
ggplot(dt2, aes(x = Season, y = Value, fill = Observation)) + 
  geom_boxplot() +                
  stat_summary(aes(ymax = ..y.., ymin = ..y..),
               fun.y = "mean", 
               geom = "errorbar",              # Use geom_errorbar to add line as mean
               color = "red", 
               width = 0.7, 
               position = position_dodge(width = 0.75), # Add the line to each group
               show.legend = FALSE)

This code creates a seasonal box plot with three observation groups (obs1, obs2, and obs3). The ggplot2 library is used to create the plot, and the stat_summary function is employed to add a red line representing the mean value for each group.

Creating a Seasonal Box Plot in MATLAB

MATLAB provides several functions and tools to create a seasonal box plot. Here’s an example code that demonstrates how to create a seasonal box plot using MATLAB:

# Define the data
dates = datesseq(ymd("1980-01-01"), ymd("1989-12-31"), 'year');
obs1 = randn(size(dates));
obs2 = 1 + 2*randn(size(dates));
obs3 = 2 + 3*randn(size(dates));

# Define the seasons
seasons = {'winter', 'spring', 'summer', 'fall'};

# Create a seasonal box plot using a loop
figure;
for i = 1:4
    subplot(2,2,i);
    boxplot(obs1(dates==dates(i)), obs2(dates==dates(i)), obs3(dates==dates(i)));
    hold on;
    mean_val = mean([obs1(dates==dates(i)); obs2(dates==dates(i)); obs3(dates==dates(i))]);
    plot(mean_val, 'ro');
    text(mean_val, max(obs1(dates==dates(i))), ['Mean (' char(i) ')'], 'Interpreter', 'none', 'HorizontalAlignment', 'center');
end

This code creates a seasonal box plot with three observation groups (obs1, obs2, and obs3). The boxplot function is used to create the box plots for each season, and the hold on command is employed to add a red dot representing the mean value for each group.

Conclusion

In this article, we explored how to create a seasonal box plot using R and MATLAB. We discussed the concept of seasonal plots and how to implement them in both programming languages. The provided example codes demonstrate how to create a seasonal box plot with three observation groups and add a red line representing the mean value for each group.

Seasonal Box Plot in R and MATLAB

Seasonal Plots Overview

Creating a Seasonal Box Plot in R

Creating a Seasonal Box Plot in MATLAB

Conclusion

Further Reading