matlab/Octave Python R Round round(a) around(a) or math.round(a) round(a) Round up ceil(a) ceil(a) ceil(a) Round down floor(a) floor(a) floor(a) Round towards zero fix(a) fix(a) 2.6 Mathematical constants Desc. The above uses A for both input and output in the call to perms_of_( ), the function perms_of_( ) uses the same name variable for input and output, and the call to perms_of_( ) is made from within another function, so inplace operations can be done by MATLAB. MATLAB commands in numerical Python (NumPy) 3 Vidar Bronken Gundersen /mathesaurus.sf.net 2.5 Round o Desc. Im actually using these permutations as the design space for an optimization problem so I need to check my cost function for every permutation (kind of a brute force method). I dont need to store the permutations at all. P perms(v) returns a matrix containing all permutations of the elements of vector v in reverse lexicographic order. E.g., calling the function like this inside another function will allow inplace operations: function some_functionĪ = perms_of_(A) % save the result of the call in a variable Here, all the permutations are generated in 1 go and then stored in the huge allstrs array. If you don't use specific inplace operation syntax in the caller then a deep copy will be returned to the caller. This syntax of using the same variable name for input and output can sometimes result in inplace operations depending on how the function is called. To be concrete, an example: Theme Copy A rand (220,1) Large vector, with one dimension a power of 2 A A. =size(A) % number of rows and columnsįor j = 1:d % permute the elements of column j Accepted Answer: Matt J I'm trying to optimize a very specific vector operation, namely taking a large (220 x 1) vector, reshaping it, permuting the indices, and reshaping once more. Perms = perms_of_(A) % save the result of the call in a variableįunction A = perms_of_(A) % declare the return variable to be A That is, you calculate a new A inside your function but you don't return it to the caller via the perms variable. example p randperm (n,k) returns a row vector containing k unique integers selected randomly from 1 to n. You are not returning the result in your function. Description example p randperm (n) returns a row vector containing a random permutation of the integers from 1 to n without repeating elements.

Matlab permute