function [x,y,Y]=levydistrintheorytest(t0,lambda,T,a,b);
% 计算理论的二维levy分布的图象 画出来的3维曲面图
% t0 ：levy walk 趋于零的时间
% lambda ：幂律值
% T：时间
% a: 离散的大步长的最大值
% b：小步长的最大值
error=0.125/180*pi; %假定平行于坐标轴的误差角度
syms u
c=-gamma(2-lambda)*t0^(lambda-1)*cos(pi*lambda/2)/lambda;
h1=20; %大的离散步长
h2=0.1; %小的离散步长
x1=-a:h1:-b;
x2=-(b-h2):h2b-h2);
x3=b:h1:a;
x=[x1,x2,x3];
disp('%%%%%%%%%%%计算的次数为%%%%%%%%%%%%%%%')
N=length(x)
y=x;
Z=zeros(N,N);
for i=1:1 %x坐标
i
for j=1:N % y坐标
theta=angle(complex(x(i),y(j)));
if theta<error && theta>-error % x轴正半轴
Z(j,i)=double(int(cos(u.*x(i)/(c*T)^(1/lambda))*exp(-(abs(u))^lambda)./pi+cos(1/u.*x(i)/(c*T)^(1/lambda))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1));
elseif theta<pi/2+error && theta>pi/2-error % y轴正半轴
Z(j,i)=double(int(cos(u.*y(j)/(c*T)^(1/lambda))*exp(-(abs(u))^lambda)./pi+cos(1/u.*y(j)/(c*T)^(1/lambda))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1));
elseif theta>pi-error || theta<-pi+error %x轴负半轴
Z(j,i)=double(int(cos(u.*x(i)/(c*T)^(1/lambda))*exp(-(abs(u))^lambda)./pi+cos(1/u.*x(i)/(c*T)^(1/lambda))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1));
elseif theta>-pi/2-error && theta<-pi/2+error %y轴负半轴
Z(j,i)=double(int(cos(u.*y(j)/(c*T)^(1/lambda))*exp(-(abs(u))^lambda)./pi+cos(1/u.*y(j)/(c*T)^(1/lambda))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1));
else
Z(j,i)=double(int(cos(u.*x(i)/(c*T)^(1/lambda)/sin(theta))*exp(-(abs(u))^lambda)./pi+cos(1/u.*x(i)/(c*T)^(1/lambda)/sin(theta))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1))*(double(int(cos(u.*y(j)/(c*T)^(1/lambda)/cos(theta))*exp(-(abs(u))^lambda)./pi+cos(1/u.*y(j)/(c*T)^(1/lambda)/cos(theta))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1)));
%zy=(double(int(cos(u.*y(j)/(c*T)^(1/lambda)/cos(theta))*exp(-(abs(u))^lambda)./pi+cos(1/u.*y(j)/(c*T)^(1/lambda)/cos(theta))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1)));
%Z(j,i)=zx*zy;
end
end
end
Y=Z;
end
错误提示；
Error using mupadmex
Error in MuPAD command: DOUBLE cannot convert the input expression into a
double array.
If the input expression contains a symbolic variable, use the VPA function
instead.
Error in sym/double (line 710)
Xstr = mupadmex('symobj::double', S.s, 0);
Error in levydistrintheorytest (line 37)
Z(j,i)=double(int(cos(u.*x(i)/(c*T)^(1/lambda)/sin(theta))*exp(-(abs(u))^lambda)./pi+cos(1/u.*x(i)/(c*T)^(1/lambda)/sin(theta))*exp(-1/(abs(u))^lambda)/u^2./pi,0,1))*(double(int(cos(u.*y(
