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用于活动识别的滑动窗口算法
我想编写一个用于活动识别的滑动窗口算法。
训练数据为,所以我认为我只需要获取(例如window_size=3 )数据的window_size并对其进行训练。稍后我也想在矩阵上使用此算法。 我是Matlab的新手,所以我需要有关如何正确实施此方法的任何建议/指导。 [B]回答:[/B] 简短的答案: %# nx = length(x) %# nwind = window_size idx = bsxfun(@plus, (1:nwind)', 1+(0:(fix(nx/nwind)-1))*nwind)-1; idx将是大小为[I]nwind-by-K[/I]的矩阵,其中[I]K[/I]是滑动窗口的数量(即,每一列包含一个滑动窗口的索引)。 请注意,在上面的代码中,如果最后一个窗口的长度小于所需的长度,则将其删除。滑动窗口也不重叠。 一个例子来说明: %# lets create a sin signal t = linspace(0,1,200); x = sin(2*pi*5*t); %# compute indices nx = length(x); nwind = 8; idx = bsxfun(@plus, (1:nwind)', 1+(0:(fix(nx/nwind)-1))*nwind)-1; %'# loop over sliding windows for k=1:size(idx,2) slidingWindow = x( idx(:,k) ); %# do something with it .. end %# or more concisely as slidingWindows = x(idx); [B]编辑:[/B] 对于重叠的窗口,让: noverlap = number of overlapping elements 然后将以上内容更改为: idx = bsxfun(@plus, (1:nwind)', 1+(0:(fix((nx-noverlap)/(nwind-noverlap))-1))*(nwind-noverlap))-1; 显示结果的示例: >> nx = 100; nwind = 10; noverlap = 2; >> idx = bsxfun(@plus, (1:nwind)', 1+(0:(fix((nx-noverlap)/(nwind-noverlap))-1))*(nwind-noverlap))-1 idx = 1 9 17 25 33 41 49 57 65 73 81 89 2 10 18 26 34 42 50 58 66 74 82 90 3 11 19 27 35 43 51 59 67 75 83 91 4 12 20 28 36 44 52 60 68 76 84 92 5 13 21 29 37 45 53 61 69 77 85 93 6 14 22 30 38 46 54 62 70 78 86 94 7 15 23 31 39 47 55 63 71 79 87 95 8 16 24 32 40 48 56 64 72 80 88 96 9 17 25 33 41 49 57 65 73 81 89 97 10 18 26 34 42 50 58 66 74 82 90 98 [url=https://stackoverflow.com/questions/2202463]更多&回答...[/url] |
所有时间均为北京时间。现在的时间是 04:54。 |
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