DATASAMPLE随机样本数据,有或没有更换。Y = DATASAMPLE(数据、K)返回K观察随机取样均匀,替代,从数据数据。如果数据是一个向量,那么Y是一个向量包含K元素选择的数据。如果数据是一个矩阵,那么Y是一个矩阵包含K行选定的数据。如果一天数组数据,DATASAMPLE样本在其第一个单体尺寸。数据可能是一个数据数组或表。因为样品是用替代,DATASAMPLE选择的观测数据可能会重复在Y Y = DATASAMPLE(数据、K、暗)返回一个样本沿着维度昏暗的数据。例如,如果数据是一个矩阵和暗淡的是2,Y包含的数据列。如果数据集是一个数组或数据表和暗淡的是2,Y包含的数据的变量。使用暗确保抽样沿着特定的维度无论数据是一个向量,矩阵或n维数组。 Y = DATASAMPLE(DATA,K, 'PARAM1',val1, 'PARAM2',val2, ...) or Y = DATASAMPLE(DATA,K,DIM, 'PARAM1',val1, 'PARAM2',val2, ...) specifies optional parameter name/value pairs to control how DATASAMPLE creates the sample. Parameters are: 'Replace' - select the sample with replacement if REPLACE is true (the default), or without replacement if REPLACE is false. When sampling without replacement, the observations that DATASAMPLE selects from DATA are unique. 'Weights' - create a weighted sample using the positive weights in the vector W. [Y,I] = DATASAMPLE(...) returns an index vector indicating which values were sampled from DATA. For example, Y = DATA(I) if DATA is a vector, Y = DATA(I,:) if DATA is a matrix, etc. DATASAMPLE uses RANDPERM and RANDI to generate random values and therefore changes the state of MATLAB's global random number generator. Control that generator using RNG. Y = DATASAMPLE(S,...) uses the random number stream S for random number generation. Examples: Draw five unique values from the integers 1:10. y = datasample(1:10,5,'Replace',false) Generate a random sequence of the characters ACGT, with replacement, according to specified probabilities. seq = datasample('ACGT',48,'Weights',[0.15 0.35 0.35 0.15]) Select a random subset of columns from a data matrix. X = randn(10,1000); Y = datasample(X,5,2,'Replace',false) Resample observations from a dataset array to create a bootstrap replicate dataset. load hospital y = datasample(hospital,size(hospital,1)) Use the second output to sample "in parallel" from two data vectors. x1 = randn(100,1); x2 = randn(100,1); [y1,i] = datasample(x1,10) y2 = x2(i) See also RAND, RANDI, RANDPERM, RNG. Documentation for datasample doc datasample Other uses of datasample tall/datasample
