MATLAB: Population growth in 7 years

exponential equationgraphpopulation growth

Hi,

I want to make a graph that will calculate how the population will change in 7 years in a spesific country. Say in 2018 there is approximately 5 million people in a country, and the growth rate is 0.63%. What will the approximated population be in 2025? Is there anyone that can help me code this.

I have already calculated this using expontential euqation:

y= a(1+r)^t

P = 5(1.0063)^7

P = 5.22 million

Best Answer

% rate
r = 0.0063;
% years
t = 7;
% initial population
a = 5e6;
% population
y = a*(1+r)^t

Related Solutions

MATLAB: First steps using dde23

There is a possible solution.

function solution
  delay=5;
  before=2; % history
  timespan=[0, 100];
  Limit=100; 
  MaxGrowthRate=0.2;
  LossRate=0.02;
  dde_options = ddeset('RelTol',1e-07);
  sol=dde23(@logistic,delay,before,timespan,dde_options,Limit,MaxGrowthRate,LossRate);
    plot(sol.x,sol.y)
    grid on
    title('Logistic Growth with delayed impact of density')
    xlabel('t')
    ylabel('y')
  end
function Change = logistic( t,Population,Z,Limit,MaxGrowthRate,LossRate )
  Loss = Population * LossRate;
  Change=Population*MaxGrowthRate*(1-Z/Limit)-Loss;
end

MATLAB: Trouble with vector length

To plot the xdata and ydata should be same. In your case t and P are of different size. Get them to same size.

%Variable key
%t is the number of years the model runs, from 1804-2300.
t = [1:496] ;
%r is the population growth rate.
r = 0.01 ;
%K is the human carrying capacity in billions of people.
K = 10 ;
%P0 is the human population in billions at the time the model begins.
P1 = 1 ;
%A is the
A = (K-P1)/P1 ;
%P is the human population in the model in billions of people.
P = (K)./(1+A*exp(-r*t)) ;
%Let 1804, the year the model begins, equal year 1.
t(1) = 1;
%Loop ensures that the the population data cycles through the model for every year and stops 496 years after the model begins, at 2300.
for  i = 1:496
    if t(i) <= 496
        % Population growth (pop_g)
        r = 0.01; 
    else
        break
    end
    
    %If-else clause takes into account the human carrying capacity of 10 billion by lowering the growth rate after the carrying capacity is reached.
    if P <=10
        r = 0.01 ;
    else
        r = .008 ;
    end
    
    %Calculate the next year of population growth using the population that was just aquired.
    P(i+1) = (r*P(i)) + P(i) ;
end
%Plot the population model data.
figure
hold on
t = linspace(1804,2300,length(P)) ;
plot (t,P)
title ('Model Population Test Graph')
legend ('Model Population')
xlabel ('Years')
ylabel ('Population')
grid on

Best Answer

Related Solutions

MATLAB: First steps using dde23

MATLAB: Trouble with vector length

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