I am struggeling with python now. i'm trying this script. I am sure this is a very common syntax in python, but it is so generic I can't find any explanation that make sense to me.
Can you help me to understand the meaning of [:, 0] and [:, 1:] in the following lines of code?
syms = np.genfromtxt('people.csv', dtype=str, delimiter=',')[:, 0]
X = np.genfromtxt('people.csv', dtype=object, delimiter=',')[:, 1:]
people.csv
| | | | |
|-------|---|---|-|
|Marc | .2| -2|A|
|Martine|-.2| 0|A|
|Max | .2| .2|A|
|Maxine | .2| .1|A|
That's using slice notation to extract specific rows and columns from the dataset.
[:, 0] means all rows, column 0.
[:, 1:] means all rows, columns 1 through n (all columns except 0).
See Understanding slicing for a good explanation of Python slicing notation.