2Â¥: Originally posted by dbb627 at 2011-11-30 22:48:21:
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fplot(@objfun,[-10 10])
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Function y=objfun(x)

y=x.^2+5*x+20;

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x=-10:0.1:10;
plot(x,objfun(x))
[ Last edited by dbb627 on 2011-11-30 at ...

4Â¥: Originally posted by dbb627 at 2011-11-30 23:30:05:
ÄãµÄtwo_minÊÇ·ñ´æÔÚÁ˵±Ç°¹¤×÷Ŀ¼ÏÂÃ棬
function y = two_min(x)
if x<=20
    y = -exp(-(x/20).^2);
else
    y = -exp(-1)+(x-20).*(x-22);
end

function y=two_min(x)
y=zeros(size(x));  %¶¨ÒåyÓëx³ß´çÏàͬ
ind=(x<=20);      %·µ»ØÒ»¸ölogicÐÍ
y(ind)=-exp(-(x(ind)/20).^2);
ind=(x>20);
y(ind)= -exp(-1)+(x(ind)-20).*(x-22);

function y=two_min(x)
y=zeros(size(x));  %¶¨ ... [/quote]


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[code]y(ind)= -exp(-1)+(x(ind)-20).*(x(ind)-22);

4Â¥: Originally posted by dbb627 at 2011-11-30 23:30:05:
ÄãµÄtwo_minÊÇ·ñ´æÔÚÁ˵±Ç°¹¤×÷Ŀ¼ÏÂÃ棬
function y = two_min(x)
if x<=20
    y = -exp(-(x/20).^2);
else
    y = -exp(-1)+(x-20).*(x-22);
end

6Â¥: Originally posted by baby_wolf at 2011-12-01 01:18:41:
×îºóÒ»¾äÔÙ¸Äһϡ£

CODE:

y(ind)= -exp(-1)+(x(ind)-20).*(x(ind)-22);

8Â¥: Originally posted by zongshengl at 2011-12-01 10:29:51:
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x=-1:0.02:1;
y=-exp(10.5*(x+0.5)).*( x<-0.5 )+...
    (exp(3.51*(x+0.5))-2*exp(-3.51*(x+0.5))).*(x>-0.5&x<0.5)...
    -exp(10.5*(x+0.5)).*(x>0.5);
plot(x,y)
figure;semilogy(x,y)

9Â¥: Originally posted by dbb627 at 2011-12-01 10:37:16:
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y=-exp(10.5*(x+0.5)) x<-0.5
y =exp(3.51*(x0.5))-2*exp(-3.51*(x+0.5))   (-0.5,0.5)
y=-exp(10.5*(x+0.5))    x>0.5

[code]
x=-1:0.02:1;
y=-exp(10.5 ...