画分段函数时出错，请高手指教

银杏树之舞

s(1,1)=677012314935207333673588073584486524245785849540281825537109375/4435885241554465269111840730175697988308235458606792704-5760367008012940040577112229466341376000000000000000/31518860350519626003857643540411700572493*z; s(1,2)=323165216575541463758898212703003640855594992552814475830078125/8871770483108930538223681460351395976616470917213585408-10286369657165964358173414695475609600000000000000000/31518860350519626003857643540411700572493*z; s(1,3)=77362058147275866072497173032197410141382946622574597783203125/100815573671692392479814562049447681552459896786518016-1645819145146554297307746351276097536000000000000000/2865350940956329636714331230946518233863*z; >> z=0:0.000001:0.00034; F=s(1,1)*(z>=0&z<0.00003)+s(1,2)*(z>=0.00003&z<0.00033)+s(1,3)*(z>=0.00033&z<=0.00034); plot(z,F); ??? Error using ==> plot Conversion to double from sym is not possible. ezplot(z,F); ??? Attempt to reference field of non-structure array. Error in ==> sym.ezplot at 60       h = ezplot(f.s,varargin{:}); 错误在哪儿，程序如何修改？

h6star

k=0;
for z=0:0.000001:0.00034;
k=k+1;
s1=677012314935207333673588073584486524245785849540281825537109375/4435885241554465269111840730175697988308235458606792704-5760367008012940040577112229466341376000000000000000/31518860350519626003857643540411700572493*z;

s2=323165216575541463758898212703003640855594992552814475830078125/8871770483108930538223681460351395976616470917213585408-10286369657165964358173414695475609600000000000000000/31518860350519626003857643540411700572493*z;

s3=77362058147275866072497173032197410141382946622574597783203125/100815573671692392479814562049447681552459896786518016-1645819145146554297307746351276097536000000000000000/2865350940956329636714331230946518233863*z;

F(k)=s1*(z>=0&z<0.00003)+s2*(z>=0.00003&z<0.00033)+s3*(z>=0.00033&z<=0.00034);
end

plot(0:0.000001:0.00034,F);

银杏树之舞

h6star 发表于 2012-4-18 13:21
k=0;
for z=0:0.000001:0.00034;
k=k+1;

我试一下
还有个问题，如何画一个z=0的三维平面？是用做辅助平面的，所以最好能够是虚平面？

银杏树之舞

h6star 发表于 2012-4-18 11:44
k=0;
for z=0:0.000001:0.00034;
k=k+1;

:)能算出来，谢谢了！

银杏树之舞

银杏树之舞 发表于 2012-4-18 15:52
我试一下
还有个问题，如何画一个z=0的三维平面？是用做辅助平面的，所以最好能够是虚平面？
...

看了别人的帖子，大概知道怎么弄了
y=1:10;
[Y,Z]=meshgrid(y);
X=zeros(size(Y));
surf(X,Y,Z);