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sequential sampling from an array to a matrix
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sequential sampling from an array to a matrix
#1
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!
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#2
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)
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