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Chapter 4: Problem 10

How can a numerical array be made to behave as a logical mask for vector operations? How can the logical attribute be removed from a numeric array?

Short Answer

Expert verified
A numerical array can be made to behave as a logical mask for vector operations by applying a condition that results in a boolean value (true or false) for each element in the array. For example, checking whether each number in the array is greater than 10 will result in a boolean mask. This mask can then be used to select or manipulate certain elements of the original array. To remove the logical attribute from a numeric array, we can convert the boolean values back into their original numerical form, typically converting True to 1 and False to 0. This creates a new numerical array without the logical mask.

Step by step solution

01

Introduction and Initialization

A logical mask is an array or list of boolean values (true or false) used to select or manipulate certain elements of another array. For this example, let's say our numerical array is [4, 9, 1, 16, 25]. Let's initialize it.
02

Convert Numerical Array to Boolean Array

In most programming languages, we can create a boolean mask from a numerical array by applying a condition that results in a boolean value. For example, we can check whether each number in the array is greater than 10. This will give us an array of booleans: [False, False, True, True, True].
03

Using the Boolean Array for vector operations

We can now use this boolean array to carry out operations on the values that meet our condition. For instance, we could use it to select only the elements in the original array that are greater than 10. Applying this mask to our original array gives us [16, 25].
04

Removing the Logical Attribute from a Numeric Array

To remove the logical attribute from an array, we can convert the boolean values back into their original numerical form. This may involve converting True to 1 and False to 0. This leaves us with a numerical array: [0, 0, 1, 1, 1]. This way, a numerical array can be treated as a logical mask for operations and then have its logical attribute removed. The specifics will vary between different programming languages, but the concepts and steps remain the same.

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Most popular questions from this chapter

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