How to make it accumarray?

Hi, may I ask that how to make it be accumulative array. I will be grateful that provide the idea. Thanks!

%% Initialize Input
K = 1*(10^-9); % Carrying Capacity of Brain Tumor
C0 = 40000; % Initial Brain Tumor Population Size
r = 4.31*(10^-3); % Growth Rate of Brain Tumor Cells
%% Model Data
t = 365; % Time in Days
C = zeros(t,1) ;
C(1) = C0;
% Calculating Brain Tumor Population 
for i=2:1:t-1
    C(i+1) = (K*(C0*exp(r*i)))/(K-C0+C0*exp(r*i));
end
hold on
nvec = 1:1:t;
%% Graph Plotting
figure(1)
title( 'Brain Tumor Population Against Time' )
xlabel('Time (Days)')
ylabel('Brain Tumor Population (cells)')
plot(nvec,C,'--bo','LineWidth',0.5,'MarkerSize',5,'MarkerEdgeColor','black')
grid
hold on

[Walter Roberson]

What would be accumulated, using what as the key value ?

I have to wonder if what you want is cumsum()

[Deck Zhan Sim]

Like the value that added to (K*(C0*exp(r*i)))/(K-C0+C0*exp(r*i)) function. It must be keep on adding.

[Mathieu NOE]

I wonder if there is a mistake in the equation

C(i+1) = (K*(C0*exp(r*i)))/(K-C0+C0*exp(r*i));

where does it come from ?

the data drops so fast it seems a bit strange (seen here in log scale )

[Deck Zhan Sim]

@Mathieu NOE This is the formula that formulated

[Deck Zhan Sim]

@Walter Roberson may i know if using cumsum(), how to apply it?

[Walter Roberson]

plot(nvec, cumsum(C), '--bo', 'LineWidth', 0.5, 'MarkerSize', 5, 'MarkerEdgeColor', 'black')