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On 05/18/2018 09:50 PM, Sharan Basappa wrote: > This is regarding numpy array. I am a bit confused how parts of the array are being accessed in the example below. > > 1 import scipy as sp > 2 data = sp.genfromtxt("web_traffic.tsv", delimiter="\t") > 3 print(data[:10]) > 4 x = data[:,0] > 5 y = data[:,1] > > Apparently, line 3 prints the first 10 entries in the array > line 4 & 5 is to extract all rows but only 1st and second columns alone for x and y respectively. > > I am confused as to how data[:10] gives the first 10 rows while data[:,0] gives all rows > Numpy ordering is [rows,columns,...]. Things you don't provide an explicit answer for are assumed to be "all", which in Python syntax is ":". The reason for THAT goes into how slices are constructed. So your example 3 could also be written print(data[0:10,:]), which sets rows to the range starting with 0 and ending before 10, and columns to everything. -- Rob Gaddi, Highland Technology -- www.highlandtechnology.com Email address domain is currently out of order. See above to fix.

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