График интеграла от двух параметров при одном фиксированном параметре

a = str2double(get(handles.edit1,'String'));
b = str2double(get(handles.edit2,'String'));
x = 0:200;
t = 0:300000;
z = 0:0.01:1;
U = exp(-x.^2./(4*a.*t.*z.^2)).*erfc(b.*t.*z.^2./(2.*sqrt(t.*(1-z.^2))))./z.^2;
F = cumtrapz(z,U)
fun = @(z)exp(-x.^2./(4*a.*t.*z.^2)).*erfc(b.*t.*z.^2./(2.*sqrt(t.*(1-z.^2))))./z.^2;
v = integral(fun,0,1);
set(handles.edit5,'String',v);
axes(handles.axes2)
plot3(x,t,F)

a = str2double(get(handles.edit1,'String'));
b = str2double(get(handles.edit2,'String'));
x = str2double(get(handles.edit3,'String'));
t = str2double(get(handles.edit4,'String'));
fun = @(z)exp(-x.^2./(4*a.*t.*z.^2)).*erfc(b.*t.*z.^2./(2.*sqrt(t.*(1-z.^2))))./z.^2;
v = quad(fun,0,1);
set(handles.edit5,'String',v);

a = str2double(get(handles.edit1,'String'));
b = str2double(get(handles.edit2,'String'));
x = str2double(get(handles.edit3,'String'));
t = 0:0.001:5;
for i = 1:length(t);
fun = @(z)exp(-x.^2./(4*a.*t.*z.^2)).*erfc(b.*t.*z.^2./(2.*sqrt(t.*(1-z.^2))))./z.^2;
v(i) = quad(fun,0,1);
end
axes(handles.axes2)
plot(t,v)