##### sequential sampling from an array to a matrix
 sequential sampling from an array to a matrix nsansen Unladen Swallow Posts: 1 Threads: 1 Joined: Mar 2020 Reputation: 0 Mar-28-2020, 02:35 PM Dear all i have an Array A A=[0 1 2 3 4 5 6 7 8 9 10 ... 200] from this array i would like to make a matrix B (pandas dataframe) where each row of B will equal 3 sequential data points from A i.e. B[0]=0 1 2 B[1]=1 2 3 B[2]=2 3 4 B[3]=3 4 5 ... B[197]=197 188 199 B[198]=198 199 200 I failed to do it with .loc and for loops due to indexing problems. Can someone help me? Thanks in advance! Reply deanhystad Da Bishop Posts: 1,052 Threads: 5 Joined: Feb 2020 Reputation: 124 Mar-29-2020, 08:15 PM (This post was last modified: Mar-29-2020, 08:15 PM by deanhystad.) Slicing in a list comprehension? ```# Make a list to slice inputs = [i for i in range(21)] # Slice it up matrix = [inputs[i:i+3] for i in range(0, len(inputs)-2)] print(matrix) ```Or a generator ```def list_slicer(the_list, slices): for i in range(0, len(inputs)-slices+1): yield the_list[i:i+slices] for row in list_slicer(inputs, 3): print(row) ``` Reply

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