index exceed matrix elements

i want data=[9 15 3000;

15 18 1800];to replace the one below

% data=[0 6 900;
%     6 7 2400;
%     7 15 3000;
%     15 18 1800;
%     18 22 3000;
%     22 24 1800];

data=[9 15 3000;
    15 18 1800];

power=data(:, 3)

power = 2×1

3000 1800

Dt=data(:,2) - data(:,1)

Dt = 2×1

6 3

Power_Generated=power.*Dt

Power_Generated = 2×1

18000 5400

Total_power1=sum(Power_Generated)

Total_power1 = 23400

Total_power2=power.*Dt;
DATA=[data(:,1) data(:,2) power];
Average_load=Total_power2/sum(Dt);
peak_load=max(power);
Daily_LF=Average_load/peak_load*100;
Results=[Average_load peak_load*ones(size(Daily_LF)) Daily_LF];
L=length(data);
timeinterval=data(:,1:2) ; 
t = sort(reshape(timeinterval,1,2*L));

Error using reshape
Number of elements must not change. Use [] as one of the size inputs to automatically calculate the appropriate size for that dimension.

for n = 1:L
    P(2*n-1) = power(n);
    P(2*n) = power(n);
end
subplot(2,1,1)
plot(t,P,'b')
xlabel(['Timer, Hr'])
ylabel(['Power, W'])
title('consumed Power, W versus time, hour')
xlim([0 24])
grid on
grid minor

Answer 1

[Voss]

Replace this:

L=length(data);

with this:

L=size(data,1);

length(data) gives the size of the longest dimension of data, which is 6 when data is 6-by-3 but is 3 when data is 2-by-3. What you really want is the size of the first dimension, i.e., the number of rows of data, so use size(data,1).

[Voss]

@Tasneem Abed: Did this answer work for you?

Answer 2

[Mathieu NOE]

Code improved below

same mistake found as @Voss

% data=[0 6 900;
%       6 7 2400;
%       7 15 3000;
%       15 18 1800;
%       18 22 3000;
%       22 24 1800];
  
data=[9 15 3000;
      15 18 1800];
  
power=data(:, 3);
Dt=data(:,2) - data(:,1);
Power_Generated=power.*Dt;
Total_power1=sum(Power_Generated);
% Total_power2=power.*Dt;  % same as 2 lines above : Power_Generated=power.*Dt;

% DATA=[data(:,1) data(:,2) power]; % what for ? this is exactly the same
% as array "data" at the beginning of your code

% Average_load=Total_power2/sum(Dt);
Average_load=Power_Generated/sum(Dt);

peak_load=max(power);
Daily_LF=Average_load/peak_load*100;
Results=[Average_load peak_load*ones(size(Daily_LF)) Daily_LF];
L=size(data,1); % get number of rows
timeinterval=data(:,1:2) ; 

t = sort(reshape(timeinterval,1,2*L)); % this works
% t = sort(timeinterval(:));                  % this works too ! (and is simpler to write)

for n = 1:L
  P(2*n-1) = power(n);
  P(2*n) = power(n);
end
subplot(2,1,1)
plot(t,P,'b')
xlabel(['Timer, Hr'])
ylabel(['Power, W'])
title('consumed Power, W versus time, hour')
xlim([0 24])
grid on
grid minor