Creating arrays from conditions

Currently, the stump diameter and trunk diameter values in tree_census are in two different columns. Living trees have a stump diameter of zero while stumps have a trunk diameter of zero. If you'd like to include both living trees and stumps in certain research calculations, it might be useful to have their diameters together in just one column.

numpy is loaded as np, and the tree_census array is available. As a reminder, the tree census columns in order refer to a tree's ID, its block ID, its trunk diameter, and its stump diameter.

This exercise is part of the course

Introduction to NumPy

Exercise instructions

Create and print a 1D array called trunk_stump_diameters, which replaces a tree's trunk diameter with its stump diameter if the trunk diameter is zero.

Hands-on interactive exercise

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

# Create and print a 1D array of tree and stump diameters
trunk_stump_diameters = ____
print(trunk_stump_diameters)

Edit and Run Code

This exercise is part of the course

Introduction to NumPy

BeginnerSkill Level

4.8+

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Meet the incredible NumPy array! Learn how to create and change array shapes to suit your needs. Finally, discover NumPy's many data types and how they contribute to speedy array operations.

Exercise 1: Introducing arrays Exercise 2: Your first NumPy array Exercise 3: Creating arrays from scratch Exercise 4: A range array Exercise 5: Array dimensionality Exercise 6: 3D array creation Exercise 7: The fourth dimension Exercise 8: Flattening and reshaping Exercise 9: NumPy data types Exercise 10: The dtype argument Exercise 11: Anticipating data types Exercise 12: A smaller sudoku game

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Exercise 1: Indexing and slicing arrays Exercise 2: Slicing and indexing trees Exercise 3: Stepping into 2D Exercise 4: Sorting trees Exercise 5: Filtering arrays Exercise 6: Filtering with masks Exercise 7: Fancy indexing vs. np.where()Exercise 8: Creating arrays from conditions

Current Exercise

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Exercise 1: Summarizing data Exercise 2: Sales totals Exercise 3: Plotting averages Exercise 4: Cumulative sales Exercise 5: Vectorized operations Exercise 6: Tax calculations Exercise 7: Projecting sales Exercise 8: Vectorizing .upper()Exercise 9: Broadcasting Exercise 10: Broadcastable or not?Exercise 11: Broadcasting across columns Exercise 12: Broadcasting across rows

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