一直就想好好学习下Mablab的,不过总给各种各样的琐事打扰,现在好了,有整整一个暑假可以研习这个经典的软件了,图书馆借了本书,翻开就有点恐怖的架式,一堆堆似懂非懂的公式和框图,不管了,先看了再说。依我的能力看懂应该是没有问题的哈,嘻嘻。
下面就开始咯,先为自己的这门自修课来道开菜:上采样和内插
当然咯,算法么还是没有研究过得啦,不过是拿采样来练练手的。
对标准sin函数的采样,x=sin(2*pi*t/10)
采样主程序:
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% File: c3_upsampex.m
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M=6;
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h=c3_lininterp(M);
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t=0:10;
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tu=0:60;
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x=sin(2*pi*t/10);
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xu=c3_upsamp(x,M);
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subplot(3,1,1)
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stem(t,x,'k.')
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ylabel('X')
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subplot(3,1,2)
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stem(tu,xu,'k.')
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ylabel('Xu')
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xi=conv(h,xu);
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subplot(3,1,3)
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stem(xi,'k.')
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ylabel('Xi')
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2
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3
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4
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5
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6
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7
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8
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9
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10
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11
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12
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13
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14
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15
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16
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17
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上采样函数:
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% File: c3_upsample.m
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function out=c3_upsamp(in,M)
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L=length(in);
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out=zeros(1,(L-1)*M+1);
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for j=1:L
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out(M*(j-1)+1)=in(j);
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end
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% End of function file.
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2
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3
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4
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5
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6
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7
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8
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线性内插函数:
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% File: c3_lininterp.m
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function h=c3_lininterp(M)
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h1=zeros(1,(M-1));
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for j=1:(M-1)
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h1(j)=j/M;
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end
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h=[0,h1,1,fliplr(h1),0]
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% End of function file.
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2
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3
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4
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5
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6
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7
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8
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生成的图形:
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不错,很能说明问题了,上采样的开销较大,线性内插的就好多了的说,嘻嘻,到这里结束^_^