Store whileloop vector values in a matrix

12 次查看(过去 30 天)
I want to store output 'steadystate' (a column vector) as a matrix as steadystate(1), steadystate(2),steadystate(3), steadystate(4).
I have not posted my whole code. Initial gues councoutGuess=[0.1;0.1;0.1;0.1] initial steadystate values = [ 0.1504734, -0.049281077, 0.14977213, 0.34987724]
while abs(steadystate-concoutGuess)>0.0000001 %Convergence error criteria for the Newton Rhapson loop
bigmatrix=alt_bigmatrix; %Using the stored symbolic matrix for the loop calculations
concoutGuess=steadystate; %Updating values
concout=steadystate;
fA= ((flowinA*concinA-flowout*concout(1))/Vol) - k1*concout(1)*concout(2); %Recalcualting values similar to previous calculations
fB= ((flowinB*concinB-flowout*concout(2))/Vol) - k1*concout(1)*concout(2) - k2*concout(2)*concout(3);
fC= ((-flowout*concout(3))/Vol) + k1*concout(1)*concout(2) - k2*concout(2)*concout(3);
fD= ((-flowout*concout(4))/Vol) + k1*concout(2)*concout(3);
molflow = [ fA; fB; fC; fD ];
bigmatrix= subs(bigmatrix); %Substituting updated values and calculating in symbolic form
differential=inv(bigmatrix);
differential=vpa(differential,8);%Evaluating symbolic and rounding to specified significant figures
molflow=vpa(molflow,8);
steadystate = concoutGuess - (differential*molflow); %Newton Rhapson formula for steady state
i=i+1;
steadystate = vpa(steadystate,8);
end

采纳的回答

Ameer Hamza
Ameer Hamza 2018-4-25
You can use save the values in a matrix as given in the code below
count = 1;
steadyStateMatrix = []
while your_condition
% your code goes here
steadyStateMatrix(:, count) = steadystate; % steadystate is a column vector
count = count + 1;
end
This will give you a steadyStateMatrix matrix, in which each column contain next iteration of steadystate.
The above code will solve your problem. However, note that steadyStateMatrix is initialized as
steadyStateMatrix = [];
this will make your code very slow if while loop has several iterations. To avoid this inefficiency, initialize your matrix, with a proper number of columns e.g.
m = #; % define m equal to number of element in 'steadystate'
steadyStateMatrix = zeros(m, 100); % 100 is a failrly large number of iterations, this will speed up your code
and add the following after end of while loop
if size(steadyStateMatrix, 2) > count
steadyStateMatrix(:, count+1:end) = [];
end

更多回答(0 个)

类别

Help CenterFile Exchange 中查找有关 Loops and Conditional Statements 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by