loop while loop for

Question

Matthew 2024-4-20

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2109571-loop-while-loop-for

Locked: Rena Berman 2024-6-5

i'm trying to get this while loop to quite based on the rate of change of v being less than .05%.

the while loop quits now just based on t(i)<7; but i'm trying to figure out how i can get this loop to stop based on ((v(2)-v(1))/(t(2)-t(1))<= 0.05.

clc
clear
m = 36/1000;
g=9.81;
T=5;
A=.00044316;
Cd=0.75;
rho=1.203;
a(1)=0;
v(1)=0;
h(1)=0;
t(1)=0;
t_step=0.001;
i=1;
u(1)=0;
while t(i)<7;
    a(i+1)= ((T)-(m*g)-(0.5*rho*A*Cd*v(i)^2))/m;
    v(i+1)= a(i+1)*t_step+v(i);
    h(i+1)= v(i+1)*t_step+h(i);
    t(i+1)=t(i)+t_step;
    
    i=i+1;
end
plot(t,v)

2 个评论
显示无隐藏无

John D'Errico 2024-4-21

编辑：John D'Errico 2024-4-21

@Matthew

iF you will remove your question once you get an answer, I'd ask you not to ask a question at all. When you remove the question, you hurt the site, because the answer is no longer meaningful. It does not allow anyone else to learn from your question and this answer. You make it less likely that your next question will find someone willing to spend the time to answer your questions.

If you think you are not supposed to ask a question like this, because your teacher would not want you to do so, then WHY DID YOU ASK THE QUESTION IN THE FIRST PLACE?

Rena Berman 2024-6-5

(Answers Dev) Restored edit

This question is locked.

Answer 1

Sulaymon Eshkabilov 2024-4-20

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2109571-loop-while-loop-for#answer_1445046

在 MATLAB Online 中打开

I suppose that what you are trying to get is dv/dt >=0.05. Here is how you can get it done:

clc; clearvars;

m = 36/1000;

g=9.81;

T=5;

A=.00044316;

Cd=0.75;

rho=1.203;

a(1)=0;

v(1)=0;

h(1)=0;

t(1)=0;

t_step=0.001;

i=1;

u(1)=0;

dvdt = 1;

while dvdt>=0.05

a(i+1)= ((T)-(m*g)-(0.5*rho*A*Cd*v(i)^2))/m;

v(i+1)= a(i+1)*t_step+v(i);

h(i+1)= v(i+1)*t_step+h(i);

t(i+1)=t(i)+t_step;

dvdt = (v(i+1)-v(i))/(t(i+1)-t(i));

i=i+1;

end

plot(t,v, 'r-.o')

grid on

text(0.5, 10, ['The simulation is halted after: ' num2str(i) ' iterations and ' num2str(t(end)) ' [seconds]'], 'backgroundcolor', 'w')

xlabel('Time, [s]')

ylabel('Velocity, [m/s]')

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Matthew 2024-4-20

Thank you, I appreciate the help.

loop while loop for

2 个评论
显示无隐藏无

采纳的回答

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

更多回答（0 个）

另请参阅

类别

标签

Community Treasure Hunt

loop while loop for

2 个评论 显示 无隐藏 无

采纳的回答

1 个评论 显示 -1更早的评论隐藏 -1更早的评论

更多回答（0 个）

另请参阅

类别

标签

Community Treasure Hunt

2 个评论
显示无隐藏无

1 个评论
显示 -1更早的评论隐藏 -1更早的评论