close all
clc
clear
%% Warmup Problem
x = linspace(-5*pi,5*pi,1000);
y1 = cos(x);
y2 = 2 * sin(x - pi/2);

figure
plot(x,y1,"r--",x,y2,"b-")
title("y1 = cos(x) and y2 = 2sin(x-pi/2)")
xlabel("x")
ylabel("y1 and y2")
legend("y1 = cos(x)", "y2 = 2sin(x-pi/2)")

%% Application Problem

%
income = readmatrix("US_Income_Inequality_Data.xlsx");
wealth = readmatrix("US_Wealth_Inequality_Data.xlsx");

figure
subplot(2,1,1)
hold on
plot(income(:,1),income(:,2),"g")
plot(income(:,1),income(:,3),"b--")
plot(income(:,1),income(:,4),"r-")
title("US Income Inequality from 1913 to 2021")
xlabel("Years")
ylabel("Percentages of population")
legend("Top 1%", "Top 10%", "Bottom 50%")
subplot(2,1,2)
hold on
plot(wealth(:,1),wealth(:,2),"g")
plot(wealth(:,1),wealth(:,3),"b--")
plot(wealth(:,1),wealth(:,4),"r-")
title("US Wealth Inequality from 1913 to 2021")
xlabel("Years")
ylabel("Percentages of population")
legend("Top 1%", "Top 10%", "Bottom 50%")

figure
hold on
plot(income(end-17:end,1),income(end-17:end,2),"g")
plot(income(end-17:end,1),income(end-17:end,3),"b--")
plot(income(end-17:end,1),income(end-17:end,4),"r-")
title("US Income Inequality from 1913 to 2021")
xlabel("Years")
ylabel("Percentages of population")
legend("Top 1%", "Top 10%", "Bottom 50%")

%%maximum,minimum, and mean
fprintf("The maximum of the bottom 50%% share of income over the years 1913 to 2021 is %.2f%%\n", max(income(:,4))*100);
fprintf("The minimum of the bottom 50%% share of income over the years 1913 to 2021 is %.2f%%\n", min(income(:,4))*100);
fprintf("The mean of the bottom 50%% share of income over the years 1913 to 2021 is %.2f%%\n", mean(income(:,4))*100)