作业帮三次样条函数源程序如何复制到matlab中求解?源程序如下：（程序中：X,Y为输入结点,dY为两端点一阶导数矩阵,x0为待求插值点,m为有效数字位数.）function[]=spline3(X,Y,dY,x0,m)N=size(X,2);s0=dY(1);sN=dY(2)
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![三次样条函数源程序如何复制到matlab中求解?源程序如下：（程序中：X,Y为输入结点,dY为两端点一阶导数矩阵,x0为待求插值点,m为有效数字位数.）function[]=spline3(X,Y,dY,x0,m)N=size(X,2);s0=dY(1);sN=dY(2)](/uploads/image/z/8802152-8-2.jpg?t=%E4%B8%89%E6%AC%A1%E6%A0%B7%E6%9D%A1%E5%87%BD%E6%95%B0%E6%BA%90%E7%A8%8B%E5%BA%8F%E5%A6%82%E4%BD%95%E5%A4%8D%E5%88%B6%E5%88%B0matlab%E4%B8%AD%E6%B1%82%E8%A7%A3%3F%E6%BA%90%E7%A8%8B%E5%BA%8F%E5%A6%82%E4%B8%8B%EF%BC%9A%EF%BC%88%E7%A8%8B%E5%BA%8F%E4%B8%AD%EF%BC%9AX%2CY%E4%B8%BA%E8%BE%93%E5%85%A5%E7%BB%93%E7%82%B9%2CdY%E4%B8%BA%E4%B8%A4%E7%AB%AF%E7%82%B9%E4%B8%80%E9%98%B6%E5%AF%BC%E6%95%B0%E7%9F%A9%E9%98%B5%2Cx0%E4%B8%BA%E5%BE%85%E6%B1%82%E6%8F%92%E5%80%BC%E7%82%B9%2Cm%E4%B8%BA%E6%9C%89%E6%95%88%E6%95%B0%E5%AD%97%E4%BD%8D%E6%95%B0.%EF%BC%89function%5B%5D%3Dspline3%28X%2CY%2CdY%2Cx0%2Cm%29N%3Dsize%28X%2C2%29%3Bs0%3DdY%281%29%3BsN%3DdY%282%29)
三次样条函数源程序如何复制到matlab中求解?源程序如下：（程序中：X,Y为输入结点,dY为两端点一阶导数矩阵,x0为待求插值点,m为有效数字位数.）function[]=spline3(X,Y,dY,x0,m)N=size(X,2);s0=dY(1);sN=dY(2)
三次样条函数源程序如何复制到matlab中求解?
源程序如下：（程序中：X,Y为输入结点,dY为两端点一阶导数矩阵,x0为待求插值点,m为有效数字位数.）
function[]=spline3(X,Y,dY,x0,m)
N=size(X,2);
s0=dY(1);sN=dY(2);
interval=0.025;
disp('x0为插值点')
x0
h=zeros(1,N-1);
for i=1:N-1 h(1,i)=X(i+1)-X(i);end
d(1,1)=6*((Y(1,2)-Y(1,1))/h(1,1)-s0)/h(1,1);
d(N,1)=6*(sN-(Y(1,N)-Y(1,N-1))/h(1,N-1))/h(1,N-1);
for i=2:N-1
d(i,1)=6*((Y(1,i+1)-Y(1,i))/h(1,i)-(Y(1,i)-Y(1,i-1))
/h(1,i-1))/(h(1,i)+h(1,i-1));end
mu=zeros(1,N-1);md=zeros(1,N-1);
md(1,N-1)=1;mu(1,1)=1;
for i=1:N-2
u=h(1,i+1)/(h(1,i)+h(1,i+1));mu(1,i+1)=u;
md(1,i)=1-u;end
p(1,1)=2;q(1,1)=mu(1,1)/2;
for i=2:N-1
p(1,i)=2-md(1,i-1)*q(1,i-1);q(1,i)=mu(1,i)/p(1,i);end
p(1,N)=2-md(1,N-1)*q(1,N-1);
y=zeros(1,N);y(1,1)=d(1)/2;
for i=2:N y(1,i)=(d(i)-md(1,i-1)*y(1,i-1))/p(1,i);end
x=zeros(1,N);x(1,N)=y(1,N);
for i=N-1:-1:1 x(1,i)=y(1,i)-q(1,i)*x(1,i+1);end
fprintf('M为三对角方程的解\n');M=x;
fprintf('\n');
syms t;
digits(m);
for i=1:N-1
pp(i)=M(i)*(X(i+1)-t)^3/(6*h(i))+M(i+1)*(t-X(i))^3
/(6*h(i))+(Y(i)-M(i)*h(i)^2/6)*(X(i+1)-t)/h(i)+
(Y(i+1)-M(i+1)*h(i)^2/6)*(t-X(i))/h(i);
pp(i)=simplify(pp(i));coeff=sym2poly(pp(i));
if length(coeff)~=4
tt=coeff(1:3);coeff(1:4)=0;coeff(2:4)=tt;end
if x0>X(i)&x0
三次样条函数源程序如何复制到matlab中求解?源程序如下：（程序中：X,Y为输入结点,dY为两端点一阶导数矩阵,x0为待求插值点,m为有效数字位数.）function[]=spline3(X,Y,dY,x0,m)N=size(X,2);s0=dY(1);sN=dY(2)
直接调用肯定不行的,你要新建一个脚本,'script',把代码复制进去,最好文件名和函数名相同, 就可以调用了