## What are indices in matlab

Indexing Arrays. Indexing into Matlab arrays is very often glossed over, but it is actually quite a powerful (and fast) technique. There are a surprising number of things that can be done by just indexing into a Matlab array. These indexing tricks come in handy to avoid "for" loops and in vectorizing code. MATLAB automatically selects those indices at which there is a logical 1 and leave out those where there is a logical 0. You can try more complex operation with logical indexing. Suppose you would like to know how much you can save by cutting down the price of all items by 10%. However you know you cannot cut your \$500 rent, so you have to do Indexing is a popular topic I write about from time to time. Today I want to focus on what happens when there are duplicate indices.ContentsAccessing Array Repeated Indexing in MATLAB » Loren on the Art of MATLAB - MATLAB & Simulink

element = get( dataset , index ) は、 index に対応する要素を返します。 getElement メソッドの構文と動作は get メソッドと同じです。 element = get( dataset , name )  Every variable in MATLAB® is an array that can hold many numbers. When you want to access selected elements of an array, use indexing. For example, consider the 4-by-4 magic square A : A = magic(4). A = 4×4 16 2 3 13 5 11 10 8 9 7 6 12  Description. mwIndex is a type that represents index values, such as indices into arrays. Use this function for cross-platform flexibility. By default, mwIndex is equivalent to size_t in C. In Fortran, mwIndex is equivalent to INTEGER*4 or  Generally one can define another variable just for storing indices. and then write your code keeping the index variable in your mind and changing it accordingly at every step. MATLAB cannot get easier than this for zero-indexed numbers. Linear Indices. A linear index allows use of a single subscript to index into an array, such as A(k). MATLAB ® treats the array as a single column vector with each column appended to the bottom of the previous column. Thus, linear indexing numbers the elements in the columns from top to bottom, left to right. Indexing into a matrix is a means of selecting a subset of elements from the matrix. MATLAB ® has several indexing styles that are not only powerful and flexible, but also readable and expressive. Indexing is a key to the effectiveness of MATLAB at capturing matrix-oriented ideas in understandable computer programs.

## The Rand index or Rand measure in statistics, and in particular in data clustering, is a measure of the similarity between two data clusterings. External links. C++ implementation with MATLAB mex files. Retrieved from

Indexing into a matrix is a means of selecting a subset of elements from the matrix. MATLAB ® has several indexing styles that are not only powerful and flexible, but also readable and expressive. Indexing is a key to the effectiveness of MATLAB at capturing matrix-oriented ideas in understandable computer programs. Indexing Arrays. Indexing into Matlab arrays is very often glossed over, but it is actually quite a powerful (and fast) technique. There are a surprising number of things that can be done by just indexing into a Matlab array. These indexing tricks come in handy to avoid "for" loops and in vectorizing code. MATLAB automatically selects those indices at which there is a logical 1 and leave out those where there is a logical 0. You can try more complex operation with logical indexing. Suppose you would like to know how much you can save by cutting down the price of all items by 10%. However you know you cannot cut your \$500 rent, so you have to do Indexing is a popular topic I write about from time to time. Today I want to focus on what happens when there are duplicate indices.ContentsAccessing Array Repeated Indexing in MATLAB » Loren on the Art of MATLAB - MATLAB & Simulink

### element = get( dataset , index ) は、 index に対応する要素を返します。 getElement メソッドの構文と動作は get メソッドと同じです。 element = get( dataset , name )

This MATLAB function returns the arrays row and col containing the equivalent row and column subscripts corresponding to the linear indices ind for a matrix of size sz. Indices in MATLAB cannot be 0, and by default, start with 1. 2) If you are using logical indexing to index into an array, be sure that your index array is of type 'logical', and not a 'double' array of 1s and 0s. Modify the index computations using the FIX, FLOOR, CEIL, or ROUND functions to ensure that the indices are integers. You can test if a variable contains an integer by comparing the variable to the output of the ROUND function operating on that variable when MATLAB is in debug mode on the line containing the variable. MATLAB - Logical Operations - MATLAB offers two types of logical operators and functions − Find indices and values of nonzero elements; locates all nonzero elements of array X, and returns the linear indices of those elements in a vector. If X is a row vector, then the returned vector is a row vector; otherwise, it returns a column vector

### element = get( dataset , index ) は、 index に対応する要素を返します。 getElement メソッドの構文と動作は get メソッドと同じです。 element = get( dataset , name )

Find indices of elements in an array based on a search from another array. Ask Question Asked 7 years, 4 months ago. Active 4 years, 9 months ago. MATLAB uses 1-based indexing, so it should read index(1) in your loop solution – Amro Jul 20 '12 at 13:38. Similar to: I was wondering if there is a quick way in matlab (pretty sure there is and I just don't know it!) to get all the values of an array at specific indices. Example: If I have an array: a = [1,3,5,7,

## element = get( dataset , index ) は、 index に対応する要素を返します。 getElement メソッドの構文と動作は get メソッドと同じです。 element = get( dataset , name )

Linear Indices. A linear index allows use of a single subscript to index into an array, such as A(k). MATLAB ® treats the array as a single column vector with each column appended to the bottom of the previous column. Thus, linear indexing numbers the elements in the columns from top to bottom, left to right. Indexing into a matrix is a means of selecting a subset of elements from the matrix. MATLAB ® has several indexing styles that are not only powerful and flexible, but also readable and expressive. Indexing is a key to the effectiveness of MATLAB at capturing matrix-oriented ideas in understandable computer programs. In MATLAB®, there are three primary approaches to accessing array elements based on their location (index) in the array. These approaches are indexing by position, linear indexing, and logical indexing. Indexing with Element Positions The most common way is to explicitly specify the indices of the elements. Every variable in MATLAB® is an array that can hold many numbers. When you want to access selected elements of an array, use indexing. For example, consider the 4-by-4 magic square A: Indexing into a matrix is the way to access its elements, rows or columns: in MATLAB there are several different approaches of this operation. At the end of this post a demonstration with several examples is available. If you are not familiar with the colon (:) operator, please have a look at MATLAB documentation. It doesn't work because MATLAB treats the subscripts as a grid, which means roughly "set all intersection of any of ii and any of jj to zero" and not "set the locations specified by these separate pairs of coordinates to zero".. In some cases (but not this one) you might need to convert a set of subscripts to indices, in which case I suggest familiarizing yourself with sub2ind.

Linear Indices. A linear index allows use of a single subscript to index into an array, such as A(k). MATLAB ® treats the array as a single column vector with each column appended to the bottom of the previous column. Thus, linear indexing numbers the elements in the columns from top to bottom, left to right. Indexing into a matrix is a means of selecting a subset of elements from the matrix. MATLAB ® has several indexing styles that are not only powerful and flexible, but also readable and expressive. Indexing is a key to the effectiveness of MATLAB at capturing matrix-oriented ideas in understandable computer programs. In MATLAB®, there are three primary approaches to accessing array elements based on their location (index) in the array. These approaches are indexing by position, linear indexing, and logical indexing. Indexing with Element Positions The most common way is to explicitly specify the indices of the elements. Every variable in MATLAB® is an array that can hold many numbers. When you want to access selected elements of an array, use indexing. For example, consider the 4-by-4 magic square A: Indexing into a matrix is the way to access its elements, rows or columns: in MATLAB there are several different approaches of this operation. At the end of this post a demonstration with several examples is available. If you are not familiar with the colon (:) operator, please have a look at MATLAB documentation. It doesn't work because MATLAB treats the subscripts as a grid, which means roughly "set all intersection of any of ii and any of jj to zero" and not "set the locations specified by these separate pairs of coordinates to zero".. In some cases (but not this one) you might need to convert a set of subscripts to indices, in which case I suggest familiarizing yourself with sub2ind. This MATLAB function returns the arrays row and col containing the equivalent row and column subscripts corresponding to the linear indices ind for a matrix of size sz.