case 'char'

if exist([fun,'.m'],'file')

syms x y z;

if nargin(str2func(fun)) == 3

f_sym = eval([fun,'(x,y,z)']); else

error('Ezimplot3:Arguments',...

'%s must be a function of 3 arguments or unknown function',fun);

end

f_text = strrep(char(f_sym),' ','');

f_hand = eval(['@(x,y,z)',vectorize(f_text),';']);

else

f_hand = eval(['@(x,y,z)',vectorize(fun),';']);

f_text = strrep(fun,'.',''); f_text = strrep(f_text,' ',''); end

case 'sym'

f_hand = eval(['@(x,y,z)',vectorize(fun),';']);

f_text = strrep(char(fun),' ','');

case {'function_handle', 'inline'}

syms x y z;

if nargin(fun) == 3 && numel(symvar(char(fun))) == 3

f_sym = fun(x,y,z);

else

error('Ezimplot3:Arguments',...

'%s must be function of 3 arguments or unknown function',char(fun));

end

f_text = strrep(char(f_sym),' ','');

f_hand = eval(['@(x,y,z)',vectorize(f_text),';']);

otherwise

error('First argument "fun" must be of type character, simbolic, function handle or inline');

end

k=1; %下面分别计算含参数的两个动态模型

syms x y z;

fk=(1/22877.17).*((x-y+k.*(3.*(x-y)/11438.59)./((2*x-y-z+8.77).^2./11438.59+(2*y-x-z+8.77).^2./11438.59+(2*z-y-x+8.77).^2./11438.59).^0.5)^2+...

(x-z+k.*(3.*(x-z)./11438.59)./((2*x-y-z+8.77).^2./11438.59+(2*y-x-z+8.77)^2./11438.59+(2*z-y-x+8.77).^2./11438.59).^0.5).^2+...

(y-z+k.*(3.*(y-z)./11438.59)./((2*x-y-z+8.77).^2./11438.59+(2*y-x-z+8.77).^2./11438.59+(2*z-y-x+8.77).^2./11438.59).^0.5).^2)+...

(1/8.77).*(x+y+z+26.31*k./((2*x-y-z+8.77).^2./11438.59+(2*y-x-z+8.77).^2./11438.59+(2*z-y-x+8.77).^2./11438.59).^0.5)-1;

f2=@(x,y,z)fk;

ezimplot3(f2,[-20000,20000]) %带参数的扩张模型

clear;

f1=@(x,y,z)((x-y).^2+(x-z).^2+(y-z).^2)/(6*20086.16)+(x+y+z)/92.4-1/105.36;

ezimplot3(f1,[-20000,20000]); %带参数的随动模型

clear %求解随动模型中单轴拉压值

k=1e-6; %10-6应变率下的单轴拉压值

syms x;

y=0;z=0;

f=((x-y).^2+(x-z).^2+(y-z).^2)/(6*20086.16)+(x+y+z)/92.4-(1+0.14*k)/105.36;

f

solve('f=0','x')

clear

k=1e-3; %10-3应变率下的单轴拉压值

syms x;

y=0;z=0;

f=((x-y).^2+(x-z).^2+(y-z).^2)/(6*20086.16)+(x+y+z)/92.4-(1+0.14*k)/105.36;

f

solve('f=0','x')

clear