Out of memory error

1 次查看（过去 30 天）
Turgut Ataseven
Turgut Ataseven 2022-1-5
评论： Turgut Ataseven 2022-1-6
Hi, please do not mind long lines because most of them are loops.
Whenever I run the code, it runs for approximately for 10-15 seconds, then displays the message at bottom and goes dark screen because I am using a laptop:
Error in Flight (line 164)
Out of memory
plot(t,u3(:)); % Flight Path Angle − Time graph
The message may not be appropriate because I typed it manually. I cannot run the code and crash my PC again, but the error line is (line 164) accurate. What should I do? Do you suggest any pre-allocations?
And there is no equations for x6 (mass). To run the code, I had to make a poor pre-allocation to define it:
x6(1,1)=W;
Should it be supported with:
x6 = zeros(1,length(t));
Thanks.
File link if you are interested: https://drive.google.com/drive/folders/1UEHR-F_cYs3N1HIqkFMXu5uXHy-GS1dj?usp=sharing
-----------------------------------------------------------------------------------------------------------------------------------------
This code tries to solve 6 ODEs with 6 state variables [horizontal position (x1 and x2), altitude (x3), the true airspeed (x4), the heading angle (x5) and the mass of the aircraft (x6)] and 3 control inputs [engine thrust (u1), the bank angle (u2) and the flight path angle (u3)] by using Euler's Method.
Different flight maneuvers are performed for the specified time intervals.
Velocities.m, Cruise_Vel.m, Des_Vel.m, Thr_cl.m, Thr_cr.m, Thr_des.m, fuel_cl.m, fuel_cr.m, fuel_des.m,den.m,drag.m,lift.m are functions in seperate tabs.
Main code (Flight.m) is:
% Climb from h1=1100 [m] to h2=1600 [m] with α=5 flight path angle.
% Perform cruise flight for t=60 minutes.
% Turn with β=30 bank angle until heading is changed by η=270◦.
% Descent from h2=1600 [m] to h1=1100 [m] with ζ=4◦ flight path angle.
% Complete a 360◦ turn (loiter) at level flight.
% Descent to h3=800 [m] with κ=4.5◦ flight path angle.
% Aircraft Properties
W = .44225E+06; % .44225E+03 tons = .44225E+06 kg
S = .51097E+03; % Surface Area [m^2]
g0 = 9.80665; % Gravitational acceleration [m/s2]
% solving 1st order ODE using numerical methods
t0=0;
tend=3960;
h=0.05;
N=(tend-t0)/h;
t=t0:h:tend;
x = zeros(6,length(t));
x3 = zeros(1,length(t));
x6(1,1)=W;
% Initial conditions
x(:,1)=[0;0;3608.92;1.0e+02 * 1.161544478045788;0;W];
for i=2:length(t)
if and (t(1,i-1) >= 0,t(1,i-1)<60) % Climb from h1=1100 [m] to h2=1600 [m] with α=5 flight path angle.
he = linspace(3608.92,5249.3,i-1);
x3(1,i-1) = he(1,i-1); % Changing altitude [m] -> [feet]
x4 = Velocities(x3(1,i-1)); % Changing speed [m/s]
x5 = 0; % Changing head angle [deg]
f = fuel_cl(x3(1,i-1)); % Changing fuel flow [kg/min]
u1 = Thr_cl(x3(1,i-1)); % Changing thrust [N]
u2 = 0; % Changing bank angle [deg]
u3 = 5; % Changing flight path angle [deg]
V_ver = x4*sin(u3); % Changing vertical speed [m/s]
C_D = drag(x3(1,i-1),x4); % Changing drag coefficient
Cl = lift(x3(1,i-1),x4); % Changing lift coefficient
p = den(x3(1,i-1)); % Changing density [kg/m3]
elseif and (t(1,i-1) >= 60,t(1,i-1)<3660) % Perform cruise flight for t=60 minutes.
x3(1,i-1) = 5249.3;
x4 = Cruise_Vel(x3(1,i-1)); % Changing speed [m/s]
x5 = 0; % Changing head angle [deg]
f = fuel_cr(x3(1,i-1)); % Changing fuel flow [kg/min]
u1 = Thr_cr(x3(1,i-1)); % Changing thrust [N]
u2 = 0; % Changing bank angle [deg]
u3 = 0; % Changing flight path angle [deg]
V_ver = x4*sin(u3); % Changing vertical speed [m/s]
C_D = drag(x3(1,i-1),x4); % Changing drag coefficient
Cl = lift(x3(1,i-1),x4); % Changing lift coefficient
p = den(x3(1,i-1)); % Changing density [kg/m3]
elseif and (t(1,i-1) >= 3660,t(1,i-1)<3720) % Turn with β=30 bank angle until heading is changed by η=270◦.
x3 (1,i-1)= 5249.3;
x4 = Cruise_Vel(x3(1,i-1)); % Changing speed [m/s]
temp = linspace(0,270,i-1);
x5 = temp(1,i-1); % Changing head angle [deg]
f = fuel_cr(x3(1,i-1)); % Changing fuel flow [kg/min]
u1 = Thr_cr(x3(1,i-1)); % Changing thrust [N]
u2 = 30; % Changing bank angle [deg]
u3 = 0; % Changing flight path angle [deg]
V_ver = x4*sin(u3); % Changing vertical speed [m/s]
C_D = drag(x3(1,i-1),x4); % Changing drag coefficient
Cl = lift(x3(1,i-1),x4); % Changing lift coefficient
p = den(x3(1,i-1)); % Changing density [kg/m3]
elseif and (t(1,i-1) >= 3720,t(1,i-1)<3900) % Descent from h2=1600 [m] to h1=1100 [m] with ζ=4◦ flight path angle.
he1 = linspace(5249.3,3608.92,i-1);
x3 (1,i-1)= he1(1,i-1);
x4 = Des_Vel(x3(1,i-1)); % Changing speed [m/s]
x5 = 270; % Changing head angle [deg]
f = fuel_des(x3(1,i-1)); % Changing fuel flow [kg/min]
u1 = Thr_des(x3(1,i-1)); % Changing thrust [N]
u2 = 0; % Changing bank angle [deg]
u3 = 4; % Changing flight path angle [deg]
V_ver = x4*sin(u3); % Changing vertical speed [m/s]
C_D = drag(x3(1,i-1),x4); % Changing drag coefficient
Cl = lift(x3(1,i-1),x4); % Changing lift coefficient
p = den(x3(1,i-1)); % Changing density [kg/m3]
elseif and (t(1,i-1) >= 3900,t(1,i-1)<=3960) % Descent to h3=800 [m] with κ=4.5◦ flight path angle.
he3 = linspace(3608.92,2624.67,i-1);
x3(1,i-1) = he3(1,i-1);
x4 = Des_Vel(x3(1,i-1)); % Changing speed [m/s]
x5 = 270; % Changing head angle [deg]
f = fuel_des(x3(1,i-1)); % Changing fuel flow [kg/min]
u1 = Thr_des(x3(1,i-1)); % Changing thrust [N]
u2 = 0; % Changing bank angle [deg]
u3 = 4.5; % Changing flight path angle [deg]
V_ver = x4*sin(u3); % Changing vertical speed [m/s]
C_D = drag(x3(1,i-1),x4); % Changing drag coefficient
Cl = lift(x3(1,i-1),x4); % Changing lift coefficient
p = den(x3(1,i-1)); % Changing density [kg/m3]
else
fprintf("A problem occured.");
end
dx1dt = x4 .* cos(x5) .* cos(u3);
dx2dt = x4 .* sin(x5) .* cos(u3);
dx3dt = x4 .* sin(u3);
dx4dt = -C_D.*S.*p.*(x4.^2)./(2.*x6)-g0.*sin(u3)+u1./x6;
dx5dt = -Cl.*S.*p.*x4./(2.*x6).*sin(u2);
dx6dt = -f;
x(1,i)= x(1,i-1) + h * dx1dt;
x(2,i)= x(2,i-1) + h * dx2dt;
x(3,i)= x(3,i-1) + h * dx3dt;
x(4,i)= x(4,i-1) + h * dx4dt;
x(5,i)= x(5,i-1) + h * dx5dt;
x(6,i)= x(6,i-1) + h * dx6dt;
end
Tot_fuel=sum(f); % Total fuel consumption during mission [kg/min]
figure(1)
plot3(x(1,:),x(2,:),x3(:)); % 3D position graph
xlabel("Horizontal Position [m]");
ylabel("Horizontal Position [m]");
zlabel("Altitude [m]");
title("3d Position Graph");
figure(2)
plot(t,x4(:)); % Vtas − Time graph
xlabel("Time [s]");
ylabel("True Air Speed [m/s]");
title("Vtas − Time graph");
figure(3)
plot(t,V_ver(:)); % V_vertical − Time graph
xlabel("Time [s]");
ylabel("Vertical Speed [m/s]");
title("Vertical Speed - Time Graph");
figure(4)
plot(t,x5(:)); % Heading − Time graph
xlabel("Time [s]");
ylabel("Heading");
title("Heading − Time graph");
figure(5)
plot(t,x6(:)); % Mass − Time graph
xlabel("Time [s]");
ylabel("Mass [kg]");
title("Mass − Time graph");
figure(6)
plot(t,u1(:)); % Thrust − Time graph
xlabel("Time [s]");
ylabel("Thrust [N]");
title("Thrust − Time graph");
figure(7)
plot(t,u2(:)); % Bank Angle − Time graph
xlabel("Time [s]");
ylabel("Bank Angle [deg]");
title("Bank Angle − Time graph");
figure(8)
plot(t,u3(:)); % Flight Path Angle − Time graph %%%%%% line 164 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
xlabel("Time [s]");
ylabel("Flight Path Angle [deg]");
title("Flight Path Angle − Time graph");
fprintf('Total fuel consumption during mission is %.2f [kg]',Tot_fuel*tend/60);
  2 个评论
Torsten
Torsten 2022-1-5
I'm really surprised that none of the inputs to your differential equations must be calculated with the help of the results for the solution variables. You always prescribe a value for x3 and calculate x4,x5,f,... for this value. Must x3(1,i-1) in your if-statements not be replaced by x(3,i-1) ???
Turgut Ataseven
Turgut Ataseven 2022-1-6
@Torsten Hi. Thanks for always replying, I finally got over it by using "Must x3(1,i-1) in your if-statements not be replaced by x(3,i-1) ???". I am open to any enchantments:
% Climb from h1=1100 [m] to h2=1600 [m] with α=5 flight path angle.
% Perform cruise flight for t=60 minutes.
% Turn with β=30 bank angle until heading is changed by η=270◦.
% Descent from h2=1600 [m] to h1=1100 [m] with ζ=4◦ flight path angle.
% Complete a 360◦ turn (loiter) at level flight.
% Descent to h3=800 [m] with κ=4.5◦ flight path angle.
% Aircraft Properties
W = .44225E+06; % .44225E+03 tons = .44225E+06 kg
S = .51097E+03; % Surface Area [m^2]
g0 = 9.80665; % Gravitational acceleration [m/s2]
% solving 1st order ODE using numerical methods
t0=0;
tend=3960;
h=0.05;
t=t0:h:tend;
N = (tend-t0)/h;
% Pre-allocations
x = zeros(6,length(t));
V_ver = zeros(1,length(t));
u1 = zeros(1,length(t));
u2 = zeros(1,length(t));
u3 = zeros(1,length(t));
% Initial conditions
x(:,1)=[0;0;3608.92;1.0e+02 * 1.161544478045788;0;W];
u1(1,1) = 707890;
u2(1,1) = 0;
u3(1,1) = 5;
for i=2:length(t)
if and (t(1,i-1) >= 0,t(1,i-1)<60) % Climb from h1=1100 [m] to h2=1600 [m] with α=5 flight path angle.
he = linspace(3608.92,5249.3,1200);
x(3,i-1) = he(1,i-1); % Changing altitude [m] -> [feet]
x(4,i-1) = Velocities(x(3,i-1)); % Changing speed [m/s]
x(5,i-1) = 0; % Changing head angle [deg]
f = fuel_cl(x(3,i-1)); % Changing fuel flow [kg/min]
u1 (1,i-1)= Thr_cl(x(3,i-1)); % Changing thrust [N]
u2 (1,i-1)= 0; % Changing bank angle [deg]
u3 (1,i-1)= 5; % Changing flight path angle [deg]
V_ver (1,i-1)= x(4,i-1)*sind(u3(1,i-1)); % Changing vertical speed [m/s]
C_D = drag(x(3,i-1),x(4,i-1)); % Changing drag coefficient
Cl = lift(x(3,i-1),x(4,i-1)); % Changing lift coefficient
p = den(x(3,i-1)); % Changing density [kg/m3]
x(3,i-1) = x(3,i-1).* 0.3048; % Changing altitude [feet] -> [m]
elseif and (t(1,i-1) >= 60,t(1,i-1)<3660) % Perform cruise flight for t=60 minutes.
x(3,i-1) = 5249.3; % Changing altitude [m] -> [feet]
x(4,i-1) = Cruise_Vel(x(3,i-1)); % Changing speed [m/s]
x(5,i-1) = 0; % Changing head angle [deg]
f = fuel_cr(x(3,i-1)); % Changing fuel flow [kg/min]
u1(1,i-1) = Thr_cr(x(3,i-1)); % Changing thrust [N]
u2(1,i-1) = 0; % Changing bank angle [deg]
u3(1,i-1) = 0; % Changing flight path angle [deg]
V_ver(1,i-1) = x(4,i-1)*sind(u3(1,i-1)); % Changing vertical speed [m/s]
C_D = drag(x(3,i-1),x(4,i-1)); % Changing drag coefficient
Cl = lift(x(3,i-1),x(4,i-1)); % Changing lift coefficient
p = den(x(3,i-1)); % Changing density [kg/m3]
x(3,i-1) = x(3,i-1).* 0.3048; % Changing altitude [feet] -> [m]
elseif and (t(1,i-1) >= 3660,t(1,i-1)<3720) % Turn with β=30 bank angle until heading is changed by η=270◦.
x(3,i-1)= 5249.3; % Changing altitude [m] -> [feet]
x(4,i-1) = Cruise_Vel(x(3,i-1)); % Changing speed [m/s]
temp = linspace(0,270,1200);
x(5,i-1) = temp(1,i-1-3660/h); % Changing head angle [deg]
f = fuel_cr(x(3,i-1)); % Changing fuel flow [kg/min]
u1(1,i-1) = Thr_cr(x(3,i-1)); % Changing thrust [N]
u2(1,i-1) = 30; % Changing bank angle [deg]
u3(1,i-1) = 0; % Changing flight path angle [deg]
V_ver(1,i-1) = x(4,i-1)*sind(u3(1,i-1)); % Changing vertical speed [m/s]
C_D = drag(x(3,i-1),x(4,i-1)); % Changing drag coefficient
Cl = lift(x(3,i-1),x(4,i-1)); % Changing lift coefficient
p = den(x(3,i-1)); % Changing density [kg/m3]
x(3,i-1) = x(3,i-1).* 0.3048; % Changing altitude [feet] -> [m]
elseif and (t(1,i-1) >= 3720,t(1,i-1)<3900) % Descent from h2=1600 [m] to h1=1100 [m] with ζ=4◦ flight path angle.
he1 = linspace(5249.3,3608.92,3600);
x(3,i-1)= he1(1,i-3720/h-1); % Changing altitude [m] -> [feet]
x(4,i-1) = Des_Vel(x(3,i-1)); % Changing speed [m/s]
x(5,i-1) = 270; % Changing head angle [deg]
f = fuel_des(x(3,i-1)); % Changing fuel flow [kg/min]
u1(1,i-1) = Thr_des(x(3,i-1)); % Changing thrust [N]
u2(1,i-1) = 0; % Changing bank angle [deg]
u3(1,i-1) = 4; % Changing flight path angle [deg]
V_ver(1,i-1) = -x(4,i-1)*sind(u3(1,i-1)); % Changing vertical speed [m/s]
C_D = drag(x(3,i-1),x(4,i-1)); % Changing drag coefficient
Cl = lift(x(3,i-1),x(4,i-1)); % Changing lift coefficient
p = den(x(3,i-1)); % Changing density [kg/m3]
x(3,i-1) = x(3,i-1).* 0.3048; % Changing altitude [feet] -> [m]
elseif and (t(1,i-1) >= 3900,t(1,i-1)<3960) % Descent to h3=800 [m] with κ=4.5◦ flight path angle.
he3 = linspace(3608.92,2624.67,1200);
x(3,i-1) = he3(1,i-3900/h-1); % Changing altitude [m] -> [feet]
x(4,i-1) = Des_Vel(x(3,i-1)); % Changing speed [m/s]
x(5,i-1) = 270; % Changing head angle [deg]
f = fuel_des(x(3,i-1)); % Changing fuel flow [kg/min]
u1(1,i-1) = Thr_des(x(3,i-1)); % Changing thrust [N]
u2 (1,i-1)= 0; % Changing bank angle [deg]
u3 (1,i-1)= 4.5; % Changing flight path angle [deg]
V_ver (1,i-1) = -x(4,i-1)*sind(u3(1,i-1)); % Changing vertical speed [m/s]
C_D = drag(x(3,i-1),x(4,i-1)); % Changing drag coefficient
Cl = lift(x(3,i-1),x(4,i-1)); % Changing lift coefficient
p = den(x(3,i-1)); % Changing density [kg/m3]
x(3,i-1) = x(3,i-1).* 0.3048; % Changing altitude [feet] -> [m]
else
fprintf("A problem occured.");
end
dx1dt = x(4,i-1) .* cos(x(5,i-1)) .* cos(u3(1,i-1)).* 0.3048;
dx2dt = x(4,i-1) .* sin(x(5,i-1)) .* cos(u3(1,i-1)).* 0.3048;
dx3dt = x(4,i-1) .* sin(u3(1,i-1));
dx4dt = -C_D.*S.*p.*(x(4,i-1).^2)./(2.*x(6,i-1))-g0.*sin(u3(1,i-1))+u1(1,i-1)./x(6,i-1);
dx5dt = -Cl.*S.*p.*x(4,i-1)./(2.*x(6,i-1)).*sin(u2(1,i-1));
dx6dt = -f;
x(1,i)= x(1,i-1) + h * dx1dt;
x(2,i)= x(2,i-1) + h * dx2dt;
x(3,i)= x(3,i-1) + h * dx3dt;
x(4,i)= x(4,i-1) + h * dx4dt;
x(5,i)= x(5,i-1) + h * dx5dt;
x(6,i)= x(6,i-1) + h * dx6dt;
end
Tot_fuel=sum(f); % Total fuel consumption during mission [kg/min]
figure(1)
plot3(x(1,:),x(2,:),x(3,:)); % 3D position graph
xlabel("Horizontal Position [m]");
ylabel("Horizontal Position [m]");
zlabel("Altitude [m]");
title("3D Position Graph");
figure(2)
plot(t,x(4,:)); % Vtas − Time graph
xlabel("Time [s]");
ylabel("True Air Speed [m/s]");
title("Vtas − Time graph");
figure(3)
plot(t([1:N]),V_ver([1:N])); % V_vertical − Time graph
xlabel("Time [s]");
ylabel("Vertical Speed [m/s]");
title("Vertical Speed - Time Graph");
figure(4)
plot(t,x(5,:)); % Heading − Time graph
xlabel("Time [s]");
ylabel("Heading");
title("Heading − Time graph");
figure(5)
plot(t,x(6,:)); % Mass − Time graph
xlabel("Time [s]");
ylabel("Mass [kg]");
title("Mass − Time graph");
figure(6)
plot(t([1:N]),u1([1:N])); % Thrust − Time graph
xlabel("Time [s]");
ylabel("Thrust [N]");
title("Thrust − Time graph");
figure(7)
plot(t([1:N]),u2([1:N])); % Bank Angle − Time graph
xlabel("Time [s]");
ylabel("Bank Angle [deg]");
title("Bank Angle − Time graph");
figure(8)
plot(t([1:N]),u3([1:N])); % Flight Path Angle − Time graph
xlabel("Time [s]");
ylabel("Flight Path Angle [deg]");
title("Flight Path Angle − Time graph");
fprintf('Total fuel consumption during mission is %.2f [kg]',Tot_fuel*tend/60);

请先登录，再进行评论。

请先登录，再回答此问题。

回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Graphics Object Programming 的更多信息

标签

产品


版本

R2021a

Community Treasure Hunt

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

Start Hunting!

Translated by