Error with ’quad‘！！！Doubleintegral?

L = 3.128438e+003；

B= 16685；

X = 2.085625e+003；

Y = 0；

Z = 0；

Quad_1 = @(Zeta,Xi) exp(-sqrt(Xi.^2 + Zeta.^2 + Z^2))./(-sqrt(Xi.^2 + Zeta.^2 + Z^2));

T_1 = quad(@(Zeta) Quad_1,Y-B,Y+B);

T_2 = @(Xi) exp(-Xi)*T_1;

T = quad(@(Xi) T_2(Xi), X-L, X+L);

disp(T);

 Error using ==> quad at 80
   The integrand function must return an output vector of the same length as the input vector
Error in ==> stationaer at 75
 T_1 = quad(@(Zeta) Quad_1,Y-B,Y+B);

Can anyone help me to correct the errors? Thanks.

Jack

Answer 1

[bym]

how about this

L = 3.128438e+003;
B= 16685;
X = 2.085625e+003;
Y = 0;
Z = 0;
Quad_1 = @(Zeta,Xi) exp(-sqrt(Xi.^2 + Zeta.^2 + Z^2))./(-sqrt(Xi.^2 + Zeta.^2 + Z^2));
%T_1 = quad(@(Zeta) Quad_1,Y-B,Y+B);
%T_2 = @(Xi) exp(-Xi)*T_1;
%T = quad(@(Xi) T_2(Xi), X-L, X+L);
T = dblquad(Quad_1,Y-B,Y+B,X-L,X+L);
disp(T);

[wang]

thanks for your answer. but the equa, that i want to have is like:

integral[_ exp(-Xi)*_integral{ exp(-sqrt(Xi^2 + Zeta^2 + Z^2))/(-sqrt(Xi^2 + Zeta^2 + Z^2))} ]

there is an exp(-Xi) before the second integral.

Answer 2

[wang]

thanks for your answer. but the equa, that i want to have is like:

integral[_ exp(-Xi)*_integral{ exp(-sqrt(Xi^2 + Zeta^2 + Z^2))/(-sqrt(Xi^2 + Zeta^2 + Z^2))} ]

there is an exp(-Xi) before the second integral.