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http://stackoverflow.com/questions/1947889/element-wise-array-replication-in-matlab
http://stackoverflow.com/questions/4918763/populate-matlab-array-with-same-values
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http://stackoverflow.com/questions/17509090/matlab-duplicate-each-element-of-a-vector
原文：http://www.cnblogs.com/sumile123/p/4936844.html