![]() ![]() If A is a nonempty, nonvector matrix, then B any (A) treats the columns of A as vectors. If A is a vector, then B any (A) returns logical 1 ( true) if any of the elements of A is a nonzero number or is logical 1, and returns logical 0 ( false) if all the elements are zero. The column number can be found by subtracting current linear index from the linear index of the first element of the current row and adding R to it. In practice, any is a natural extension of the logical OR operator. If astuple is True, one 1-D tensor for each dimension, containing the indices of each nonzero element along that dimension. ![]() Another difference between Scilab and Matlab is that Matlab returns column. Returns: If astuple is False, the output tensor containing indices. You can use those logical values to index into an array. For example, in i,j,vfind (X), v is equal to: X (i+ (j-1))size (X,1). Certain MATLAB functions and operators return logical values to indicate fulfillment of a condition. ![]() R = N + 1 -floor(r) įor the column number we find the index of the first element idx_first of the current row R: idx_first=(floor(r+1). Note that Scilab function can only return two output values and Matlab one can return a third value that can be computed according to the first two output matrices as explained in Matlab help. R can be rounded and subtracted from N to get the first element (row number of triangular matrix) of the desired output. Given jj = size(I,1) + 1 - ii as a row index I that begins from the end of I and using N * (N -1) / 2 we can formulate a quadratic equation: N * (N -1) / 2 = jj The find function is also useful in determining which elements of a matrix meet a specified condition. ![]() The functions any and all are useful for determining whether any or all of the elements of a matrix satisfy some condition. find (X) returns a vector containing the linear indices of each nonzero element in array X. We can get the number of rows of I with the Gauss formula for triangular number (N-1) * (N-1+1) /2 = Non-zero element means any number or a single value you want to find In Array you have search 1D array which does similar thing what you want. 16.1 Finding Elements and Checking Conditions. Thus, the find method has a running time dictated by the overhead of copying the array and calling find, whereas the loop method time is dictated by how many array elements one needs to visit to find the first non-zero element.The I matrix can be generated by nchoosek. i,j find (X) returns the row and column indices of the nonzero entries in the matrix X. If none is found, find returns an empty matrix. first create array X so as for even number in v X is one and zero for the others : X (mod (v,2)0) then use find to find desired indices : idxevenfind (X) Share. q is the location of the first non-zero element. Description k find (X) returns the indices of the array X that point to nonzero elements. k find (X) returns a vector containing the linear indices of each nonzero element in array X. Test results depend, of course, on the expected number of elements to visit before a non-zero element is found, as well as on the array length n. Sometimes it is useful to simultaneously change the values of several existing array elements. In this video you will learnhow to find the indices of non zero elements in a matrix in matlab,how to find the indixes of non zero elements in a matrix in ma. (I didn't add the bwconncomp answer because it's significantly slower). function to get the index of the element equal to 8 that satisfies the conditions. Method2 is the fixed version of this answer, using find and copying the array. ![]()
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