# Indexing And Slicing Numpy Arrays

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# Import modules import numpy as np

# Create a 2x2 array battle_deaths = [[344, 2345], [253, 4345]] deaths = np.array(battle_deaths) deaths

array([[5341, 2345], [ 253, 4345]])

# Select the top row, second item deaths[0, 1]

2345

# Select the second column deaths[:, 1]

array([2345, 4345])

# Select the second row deaths[1, :]

array([ 253, 4345])

# Create an array of civilian deaths civilian_deaths = np.array([4352, 233, 3245, 256, 2394]) civilian_deaths

array([4352, 233, 3245, 256, 2394])

# Find the index of battles with less than 500 deaths few_civ_deaths = np.where(civilian_deaths < 500) few_civ_deaths

(array([1, 3]),)

# Find the number of civilian deaths in battles with less than 500 deaths civ_deaths = civilian_deaths[few_civ_deaths] civ_deaths

array([233, 256])