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”
Exercise instructions
- Import the
numpy
package under the local aliasnp
. - Write a
for
loop that iterates over all elements innp_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 thenp_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