清晰的所有;
g = 9.807;
韦尔= 100;th_deg = 30;
x0 = 0;y0 = 0;
t0=0;tf=100;
vx =韦尔* cosd (th_deg);
v =韦尔*信德(th_deg);
fx=@(t,x,u)u;
傅= @ (t, x, u) 0;
fy=@(t,y,v)v;
阵线= @ (t y v) - g;
t (1) = 0;
x(1)=0;y(1)=0;
x_exact (1) = 0; y_exact (1) = 0;
u(1)=vx;v(1)=vy;
h = 0.001;
N =装天花板(tf-t (1)) / h);
为j=1:N
t (j + 1) = t (j) + h;
x_exact (j + 1) = vx * t (j + 1);
精确(j+1)=vy*t(j+1)-g*0.5*(t(j+1))^2;
k1x =外汇(t (j) x (j), u (j));
k1u=fu(t(j),x(j),u(j));
k1y =财政年度(t (j), y (j), v (j));
k1v =阵线(t (j), y (j), v (j));
k2x =外汇(t (j) + h x (j) + k1x u (j) + k1u);
傅k2u = (t (j) + h, x (j) + k1x u (j) + k1u);
k2y =财政年度(t (j) + h, y (j) + k1y v (j) + k1v);
k2v =阵线(t (j) + h, y (j) + k1y v (j) + k1v);
k3x=fx(t(j)+h/2,x(j)+(3*k1x+k2x)/8),u(j)+(3*k1u+k2u)/8);
k3u=fu(t(j)+h/2,x(j)+(3*k1x+k2x)/8),u(j)+(3*k1u+k2u)/8);
k3y =财政年度(t (j) + h / 2, y (j) + ((3 * k1y + k2y) / 8), v (j) + ((3 * k1v + k2v) / 8));
k3v =阵线(t (j) + h / 2, y (j) + ((3 * k1y + k2y) / 8), v (j) + ((3 * k1v + k2v) / 8));
k4x =外汇(t (j) + 2 * h / 3、x (j) + (8 * k1x + 2 * k2x + 8 * k3x) / 27日u (j) + (8 * k1u + 2 * k2u + 8 * k3u) / 27);
傅k4u = (t (j) + 2 * h / 3、x (j) + (8 * k1x + 2 * k2x + 8 * k3x) / 27日u (j) + (8 * k1u + 2 * k2u + 8 * k3u) / 27);
k4y =财政年度(t (j) + 2 * h / 3, y (j) + (8 * k1y + 2 * k2y + 8 * k3y) / 27 v (j) + (8 * k1v + 2 * k2v + 8 * k3v) / 27);
k4v=fv(t(j)+2*h/3,y(j)+(8*k1y+2*k2y+8*k3y)/27,v(j)+(8*k1v+2*k2v+8*k3v)/27);
k5x=fx(t(j)+(7-(21)^0.5)*h/14,x(j)+(3*(3*(21)^0.5-7)*k1x-8*(7-(21)^0.5)*k2x+48*(7-(21)^0.5)*k3x-3*(21-(21)^0.5)*k4x)/392,u(j)+3*(3*(3*(3*(3*(21)^0.5-7*(21)^0.5)/k8u-8*(7-(21)^0.5)*+48*(7-(7-(21)^0.5)/k21)/k2u*0.5*(21)/k21)/k21);
傅k5u = (t (j) + (7 - (21) ^ 0.5) * h / 14日x (j) + (3 * 3 * 7 (21) ^ 0.5) * k1x-8 * (7 - (21) ^ 0.5) * k2x + 48 * (7 - (21) ^ 0.5) * k3x-3 * (21 - (21) ^ 0.5) * k4x) / 392, u (j) + 3 * ((3 * 7 (21) ^ 0.5) * k1u-8 * (7 - (21) ^ 0.5) * k2u + 48 * (7 - (21) ^ 0.5) * k3u-3 * (21 - (21) ^ 0.5) * k4u) / 392);
k5y=fy(t(j)+(7-(21)^0.5)*h/14,y(j)+(3*(3*(21)^0.5-7)*k1y-8*(7-(21)^0.5)*k2y+48*(7-(21)^0.5)*k3y-3*(21-(21)^0.5)*k4y)/392,v(j)+3*(3*(3*(3*(21)^0.5-7*(7-(21)^0.5)*+48*(7-(7-(21)^0.5)/k3y-5*(21)/k21)/k2*(21)/k21);
k5v=fv(t(j)+(7-(21)^0.5)*h/14,y(j)+(3*(3*(21)^0.5-7)*k1y-8*(7-(21)^0.5)*k2y+48*(7-(21)^0.5)*k3y-3*(21-(21)^0.5)*k4y)/392,v(j)+3*(3*(3*(3*(21)^0.5-7*(7-(21)^0.5)*+48*(7-(21)^0.5)/k3y*(21)^0.5)*(k21)/k2y)/k21);
k6x =外汇(t (j) + (7 + (21) ^ 0.5) * h / 14日x (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1x-40 * (7 + (21) ^ 0.5) * k2x - 320 * (21) ^ 0.5 * k3x + 3 * (21 + 121 * (21) ^ 0.5) * k4x + 392 * (6 + (21) ^ 0.5) * k5x) / 1960 u (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1u-40 * (7 + (21) ^ 0.5) * k2u - 320 * (21) ^ 0.5 * k3u + 3 * (21 + 121 * (21) ^ 0.5) * k4u + 392 * (6 + (21) ^ 0.5) * k5u) / 1960);
傅k6u = (t (j) + (7 + (21) ^ 0.5) * h / 14日x (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1x-40 * (7 + (21) ^ 0.5) * k2x - 320 * (21) ^ 0.5 * k3x + 3 * (21 + 121 * (21) ^ 0.5) * k4x + 392 * (6 + (21) ^ 0.5) * k5x) / 1960 u (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1u-40 * (7 + (21) ^ 0.5) * k2u - 320 * (21) ^ 0.5 * k3u + 3 * (21 + 121 * (21) ^ 0.5) * k4u + 392 * (6 + (21) ^ 0.5) * k5u) / 1960);
k6y =财政年度(t (j) + (7 + (21) ^ 0.5) * h / 14日y (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1y-40 * (7 + (21) ^ 0.5) * k2y - 320 * (21) ^ 0.5 * k3y + 3 * (21 + 121 * (21) ^ 0.5) * k4y + 392 * (6 + (21) ^ 0.5) * k5y) / 1960 v (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1v-40 * (7 + (21) ^ 0.5) * k2v - 320 * (21) ^ 0.5 * k3v + 3 * (21 + 121 * (21) ^ 0.5) * k4v + 392 * (6 + (21) ^ 0.5) * k5v) / 1960);
k6v =阵线(t (j) + (7 + (21) ^ 0.5) * h / 14日y (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1y-40 * (7 + (21) ^ 0.5) * k2y - 320 * (21) ^ 0.5 * k3y + 3 * (21 + 121 * (21) ^ 0.5) * k4y + 392 * (6 + (21) ^ 0.5) * k5y) / 1960 v (j) + (5 * (231 + 51 * (21) ^ 0.5) * k1v-40 * (7 + (21) ^ 0.5) * k2v - 320 * (21) ^ 0.5 * k3v + 3 * (21 + 121 * (21) ^ 0.5) * k4v + 392 * (6 + (21) ^ 0.5) * k5v) / 1960);
k7x =外汇(t (j) + h x (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1x + 120 * k2x + 40 * (7 * (21) ^ 0.5 5) * k3x - 63 * (3 * 0.5 (21) ^ 2) * k4x-14 * (49 + 9 * (21) ^ 0.5) * k5x + 70 * (7 - (21) ^ 0.5) * k6x) / 180 u (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1u + 120 * k2u + 40 * (7 * (21) ^ 0.5 5) * k3u - 63 * (3 * 0.5 (21) ^ 2) * k4u-14 * (49 + 9 * (21) ^ 0.5) * k5u + 70 * (7 - (21) ^ 0.5) * k6u) / 180);
傅k7u = (t (j) + h x (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1x + 120 * k2x + 40 * (7 * (21) ^ 0.5 5) * k3x - 63 * (3 * 0.5 (21) ^ 2) * k4x-14 * (49 + 9 * (21) ^ 0.5) * k5x + 70 * (7 - (21) ^ 0.5) * k6x) / 180, u (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1u + 120 * k2u + 40 * (7 * (21) ^ 0.5 5) * k3u - 63 * (3 * 0.5 (21) ^ 2) * k4u-14 * (49 + 9 * (21) ^ 0.5) * k5u + 70 * (7 - (21) ^ 0.5) * k6u) / 180);
k7y =财政年度(t (j) + h, y (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1y + 120 * k2y + 40 * (7 * (21) ^ 0.5 5) * k3y - 63 * (3 * 0.5 (21) ^ 2) * k4y-14 * (49 + 9 * (21) ^ 0.5) * k5y + 70 * (7 - (21) ^ 0.5) * k6y) / 180 v (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1v + 120 * k2v + 40 * (7 * (21) ^ 0.5 5) * k3v - 63 * (3 * 0.5 (21) ^ 2) * k4v-14 * (49 + 9 * (21) ^ 0.5) * k5v + 70 * (7 - (21) ^ 0.5) * k6v) / 180);
k7v =阵线(t (j) + h, y (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1y + 120 * k2y + 40 * (7 * (21) ^ 0.5 5) * k3y - 63 * (3 * 0.5 (21) ^ 2) * k4y-14 * (49 + 9 * (21) ^ 0.5) * k5y + 70 * (7 - (21) ^ 0.5) * k6y) / 180 v (j) + (15 * (22 + 7 * (21) ^ 0.5) * k1v + 120 * k2v + 40 * (7 * (21) ^ 0.5 5) * k3v - 63 * (3 * 0.5 (21) ^ 2) * k4v-14 * (49 + 9 * (21) ^ 0.5) * k5v + 70 * (7 - (21) ^ 0.5) * k6v) / 180);
x(j+1)=x(j)+h*(9*k1x+64*k3x+49*k5x+49*k6x+9*k7x)/180;
u(j+1)=u(j)+h*(9*k1u+64*k3u+49*k5u+49*k6u+9*k7u)/180;
y(j+1)=y(j)+h*(9*k1y+64*k3y+49*k5y+49*k6y+9*k7y)/180;
v(j+1)=v(j)+h*(9*k1v+64*k3v+49*k5v+49*k6v+9*k7v)/180;
如果(y(j+1)<0)
打破;
结束
结束
hmax = max (y);
征求= max (x);
情节(x, y);
持有在;
情节(x_exact y_exact);
包含(“X”);
ylabel (“Y”);