做网站邢台,用dw做网站怎么给链接,十堰市建设工程管理处网站,贵阳市住房和城乡建设厅网站产生均值为0#xff0c;方差 σ^2 1#xff0c;标准差σ 1的正态分布的随机数或矩阵的函数。Example:产生一个随机分布的指定均值和方差的矩阵#xff1a;将randn产生的结果乘以标准差#xff0c;然后加上期望均值即可。例如#xff0c;产生均值为0.6#xff0c;方差为…产生均值为0方差 σ^2 1标准差σ 1的正态分布的随机数或矩阵的函数。Example:产生一个随机分布的指定均值和方差的矩阵将randn产生的结果乘以标准差然后加上期望均值即可。例如产生均值为0.6方差为0.1的一个5*5的随机数方式如下x .6 sqrt(0.1) * randn(5)x 0.8713 0.4735 0.8114 0.0927 0.76720.9966 0.8182 0.9766 0.6814 0.66940.0960 0.8579 0.2197 0.2659 0.30850.1443 0.8251 0.5937 1.0475 -0.08640.7806 1.0080 0.5504 0.3454 0.5813其他类似函数rand, randperm, sprand, sprandnrandnNormally distributed random numbers and arraysSyntaxY randn(n)Y randn(m,n)Y randn([m n])Y randn(m,n,p,...)Y randn([m n p...])Y randn(size(A))randns randn(state)DescriptionThe randn function generates arrays of random numbers whose elements are normally distributed with mean 0, variance σ^2 1 , and standard deviation σ 1.Y randn(n) returns an n-by-n matrix of random entries. An error message appears if n is not a scalar. Y randn(m,n) or Y randn([m n]) returns an m-by-n matrix of random entries. Y randn(m,n,p,...) or Y randn([m n p...]) generates random arrays. Y randn(size(A)) returns an array of random entries that is the same size as A. randn, by itself, returns a scalar whose value changes each time its referenced. s randn(state) returns a 2-element vector containing the current state of the normal generator. To change the state of the generator: randn(state,s)Resets the state to s. randn(state,0)Resets the generator to its initial state. randn(state,j)For integer j, resets the generator to its jth state. randn(state,sum(100*clock))Resets it to a different state each time.ExamplesExample 1. R randn(3,4) may produce R 1.1650 0.3516 0.0591 0.87170.6268 -0.6965 1.7971 -1.44620.0751 1.6961 0.2641 -0.7012For a histogram of the randn distribution, see hist. Example 2. Generate a random distribution with a specific mean and variance . To do this, multiply the output of randn by the standard deviation , and then add the desired mean. For example, to generate a 5-by-5 array of random numbers with a mean of .6 that are distributed with a variance of 0.1 x .6 sqrt(0.1) * randn(5)x 0.8713 0.4735 0.8114 0.0927 0.76720.9966 0.8182 0.9766 0.6814 0.66940.0960 0.8579 0.2197 0.2659 0.30850.1443 0.8251 0.5937 1.0475 -0.08640.7806 1.0080 0.5504 0.3454 0.5813See Also rand, randperm, sprand, sprandn[本帖最后由 treeman 于 2010-10-14 22:22 编辑]
