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])
```