[Solved] Consider arr = np.array([10, 20, 30, 40, 50, 60, 70]). What is the result of arr[4:1:1]? — Ans: An empty array because the step is positive but start > stop. | NumPy

NumPy - Indexing and Slicing

Consider arr = np.array([10, 20, 30, 40, 50, 60, 70]). What is the result of arr[4:1:1]?

A[20, 30, 40, 50]

B[50, 40, 30]

CAn empty array because the step is positive but start > stop.

DAn error due to invalid slice parameters.

Step-by-Step Solution

Solution:

Step 1: Analyze slice parameters
Start index is 4, stop index is 1, step is +1.
Step 2: Understand slicing behavior
With positive step, slicing moves forward; since start > stop, no elements are selected.
Final Answer:
An empty array because the step is positive but start > stop. -> Option C
Quick Check:
Positive step requires start < stop [OK]

Quick Trick: Positive step needs start < stop to select elements [OK]

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