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Loop over NumPy array

If you're dealing with a 1D NumPy array, looping over all elements can be as simple as:

for x in my_array :
    ...

If you're dealing with a 2D NumPy array, it's more complicated. A 2D array is built up of multiple 1D arrays. To explicitly iterate over all separate elements of a multi-dimensional array, you'll need this syntax:

for x in np.nditer(my_array) :
    ...

Two NumPy arrays that you might recognize from the intro course are available in your Python session: np_height, a NumPy array containing the heights of Major League Baseball players, and np_baseball, a 2D NumPy array that contains both the heights (first column) and weights (second column) of those players.

This is a part of the course

“Intermediate Python”

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Exercise instructions

  • Import the numpy package under the local alias np.
  • Write a for loop that iterates over all elements in np_height and prints out "x inches" for each element, where x is the value in the array.
  • Write a for loop that visits every element of the np_baseball array and prints it out.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Import numpy as np


# For loop over np_height


# For loop over np_baseball
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