Question

How can I get my while loop to run until my condition in my if statement is met? (In MATLAB)

clc%clears screen

clear all%clears history

close all%closes all files

format long

%Euler's Method

%Initial conditions and setup

%Projectile motion

x=3;%randi(3);

y=3;%randi(3);

figure('color','white');

plot(x,y,'bo');

hold on

wind = (-10 + 20*rand(1));

fprintf('The wind speed is %2.2i\n',wind);

v0= input('Initial velocity(m/s): ');

a= input('Angle of projection(in degrees): ');

a=a*pi/180;

h=.01;

cd=.1;

%cdy=.1;

%cdx=(rand*2-1)/2;

%cdy=(rand*2-1)/2;

m=1.5;

g=9.8; %acceleration due to gravity in m/s^2

%td=2*v0*sin(a)/g; %total time

x1=0;

y1=0;

t=0;

r=4;

while y1 >= 0 %y1 >=0

plot(x1,y1,'o','MarkerFaceColor','b','MarkerSize',8)

hold all

xlabel('Distance in meter');

ylabel('Height in meter');

xlim([0 30]);

ylim([0 30]);

getframe;

fd=(v0*cos(a))*cd+(wind);

x1=x1+(h*(v0*cos(a)+ fd*t));%(cd*t + wind))); %Euler's method for x

y1=y1+h*(v0*sin(a)-g*t-(cd/m)*t); %Euler's method for y

t=t+h;

if abs(x1-x) <= .25 && abs(y1-y) <= .25

fprintf('Congratulations you hit the target!')

break

end

end

Answer 1

%the script now asks for input as long as the target is not hit

clc%clears screen
clear all%clears history
close all%closes all files
format long
%Euler's Method
%Initial conditions and setup
%Projectile motion
x=3;%randi(3);
y=3;%randi(3);
figure('color','white');
plot(x,y,'bo');
hold on
wind = (-10 + 20*rand(1));
fprintf('The wind speed is %2.2i\n',wind);
h=.01;
cd=.1;
%cdy=.1;
%cdx=(rand*2-1)/2;
%cdy=(rand*2-1)/2;
m=1.5;
g=9.8; %acceleration due to gravity in m/s^2
%td=2*v0*sin(a)/g; %total time
k=1;
while k==1
v0= input('Initial velocity(m/s): ');
a= input('Angle of projection(in degrees): ');
a=a*pi/180;
x1=0;
y1=0;
t=0;
r=4;
while y1 >= 0 %y1 >=0
plot(x1,y1,'o','MarkerFaceColor','b','MarkerSize',8)
hold all
xlabel('Distance in meter');
ylabel('Height in meter');
xlim([0 30]);
ylim([0 30]);
getframe;
fd=(v0*cos(a))*cd+(wind);
x1=x1+(h*(v0*cos(a)+ fd*t));%(cd*t + wind))); %Euler's method for x
y1=y1+h*(v0*sin(a)-g*t-(cd/m)*t); %Euler's method for y
t=t+h;
if abs(x1-x) <= .25 && abs(y1-y) <= .25
fprintf('Congratulations you hit the target!')
k=0;
break
end
end
end