Array Indices Must Be Positive Integers Or Logical Values. Update

This error message typically occurs in programming languages like Python, MATLAB, or R when you try to access an array using an index that is not a positive integer or a logical value.

For example, in Python, you might get this error message if you try to access an element of a list using a string as the index:

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my_list = [1, 2, 3]
print(my_list['foo'])

In MATLAB, you might get this error message if you try to access an element of an array using a negative index:

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my_array = [1, 2, 3]
my_array(-1) % This will give an error

To resolve this error, make sure that you only use positive integers or logical values as indices when accessing arrays. If you need to use a non-integer index, make sure that it is a valid data type for indexing in your programming language.

Indices are typically used to refer to specific elements within an array or matrix. In most programming languages, including MATLAB and Python, indices must be real positive integers or logicals.

Real positive integers are whole numbers greater than zero, such as 1, 2, 3, and so on. These are commonly used to access elements in an array or matrix.

Logicals, also known as Boolean values, are either true or false. They are often used to represent logical conditions, such as whether an element meets a certain criteria. In MATLAB, for example, logical indexing can be used to extract elements from an array that meet a certain condition, such as all elements that are greater than a certain value.

It’s important to note that some programming languages may have slightly different rules regarding indices. For example, in some languages, indices may start from 0 instead of 1. However, in general, indices are either real positive integers or logicals.

In MATLAB, an array index is a positive integer used to specify a particular element of an array. Arrays in MATLAB are indexed using parentheses or brackets, with the indices separated by commas or spaces.

For example, consider the following 2D array:

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A = [1 2 3;     4 5 6;     7 8 9];

To access the element in the second row and third column of A, you would use the following index:

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A(2, 3)

This would return the value 6, which is located in the second row and third column of A.

Indices in MATLAB always start at 1, so the first element of an array is always accessed using an index of 1. If you try to access an element with an index that is out of range (i.e., less than 1 or greater than the size of the array in that dimension), MATLAB will return an error.

In MATLAB, subscript indices refer to the indices used to access elements of an array or matrix. These indices must be either real positive integers or logical values.

A real positive integer is a non-zero, whole number greater than or equal to 1. For example, 1, 2, 3, 4, etc.

A logical value is a true or false value, represented in MATLAB by the keywords true and false, respectively. Logical values can also be represented using numeric values, where 1 represents true and 0 represents false.

The error message “Subscript indices must either be real positive integers or logicals” usually occurs when you try to access an element of an array or matrix using an invalid index. This can happen if you use a non-integer value or a negative value as an index.

To fix the error, make sure that the indices you use are either real positive integers or logicals.

This error message usually occurs when you are trying to access an array element using an index that is not a positive integer or a logical value.

In many programming languages, arrays are zero-indexed, meaning the first element has an index of 0, the second element has an index of 1, and so on. Therefore, if you try to access an element with an index less than 0 or a non-integer value, you will get this error message.

For example, in Python, if you have an array arr and you try to access an element with an index of -1 or 1.5, you will get this error message:

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arr = [1, 2, 3]
print(arr[-1])  # This will give an error because the index is negative
print(arr[1.5]) # This will give an error because the index is not an integer

Similarly, in MATLAB, if you have an array A and you try to access an element with an index of -1 or a non-integer value, you will get this error message:

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A = [1, 2, 3];
disp(A(-1));   % This will give an error because the index is negative
disp(A(1.5));  % This will give an error because the index is not an integer

To fix this error, make sure that you are using a positive integer or a logical value as the index when accessing elements of an array.

This error message usually occurs in programming when you try to access an array or list using an index that is not a positive integer or logical value. In most programming languages, array indices start at 0, which means that the first element of an array has an index of 0, the second element has an index of 1, and so on.

For example, if you have an array called myArray with three elements, you can access the first element using myArray[0], the second element using myArray[1], and the third element using myArray[2].

If you try to access an element using an index that is less than 0 or not an integer, you will get an “invalid array indices” error. For example, if you try to access myArray[-1] or myArray[2.5], you will get this error.

To fix this error, make sure that you are using a valid integer index to access the array.