请问这是matlab解常微分方程的哪一种方法
clc
clear all
g=9.8;
m=1;
C=0.5;
r=0.05;
A=pi*r^2;
rou=1.2;
D=(rou*C*A)/2;
detat=0.01;
theta=(35/180*pi);
x(1)=0;
y(1)=0;
V(1)=50;
Vx(1)=V(1)*cos(theta);
Vy(1)=V(1)*sin(theta);
N=700;
for n=1:N
V(n)=sqrt(Vx(n)^2+Vy(n)^2)
ax(n)=-(D/m)*V(n)*Vx(n);
ay(n)=-g-(D/m)*V(n)*Vy(n);
Vx(n+1)=Vx(n)+ax(n)*detat;
Vy(n+1)=Vy(n)+ay(n)*detat;
x(n+1)=x(n)+Vx(n)*detat+0.5*ax(n)*detat^2;
y(n+1)=y(n)+Vy(n)*detat+0.5*ay(n)*detat^2;
px(n)=Vx(1)*n*detat;
py(n)=Vy(1)*n*detat-0.5*g*(n*detat)^2;
end
plot(x,y,'r',px,py,'g');
grid
xlabel('x'),ylabel('y');
title('有空气阻力的抛射体运动')