How to use 'find' function in matlab

2017 3 28
1 个回答
回答已采纳
更新时间：2017 3 28
4 次查看（30 天）

0 个投票

In the below code, We have a random population with structures Position (3D array) and Cost. I need to check whether a particular element present in the population If it does then I want to remove it from the population. I'm using 'find' function for doing it. It was working fine with arrays but with structures I'm getting error below error
_ Undefined operator '~=' for input arguments of type 'struct'_
Here is the code
clc; clear all;
varMin = -5;
varMax = 5;
D = 3;
VarSize = [1 D]; % Decision Variables Matrix Size
NP = 3;
empty_individual.Position = [];
empty_individual.Cost = [];
P = repmat(empty_individual, NP, 1);
addpath('E:\Dimensionality Reduction\DR & Optimization\Data\Objective Functions');
CostFunction = @(x) sphere(x);
%%Generating random population
for i = 1:NP
P(i).Position = unifrnd(varMin, varMax, VarSize);
P(i).Cost = CostFunction(P(i).Position);
end
xi = [1 1 1]; % xig
P = P(find(P ~= xi));

4 个评论
显示 2更早的评论 隐藏 2更早的评论

KSSV
KSSV 2017-3-28
You cannot use find like that. _P is 3x1 structure, what you want to find exactly?
Atinesh Singh
Atinesh Singh 2017-3-28
Can you suggest any alternative for it.
KSSV
KSSV 2017-3-28
You have to mention what you are expecting actually?
Atinesh Singh
Atinesh Singh 2017-3-28
I need to check whether a particular element present in the population If it does then I want to remove it from the population

请先登录，再进行评论。

请先登录，再回答此问题。

 采纳的回答

KSSV
KSSV 2017-3-28

0 个投票

idx = 1:length(P) ;
P = P(find(idx ~= xi));

6 个评论
显示 4更早的评论 隐藏 4更早的评论

Atinesh Singh
Atinesh Singh 2017-3-28
Its not working "I need to check whether a particular element present in the population If it does then I want to remove it from the population"
KSSV
KSSV 2017-3-28
Your xi is [1 1 1]..P has indices [1 2 3]. [1] is common with xi and P, so the above code picks up only [2 3] indices of P.
Atinesh Singh
Atinesh Singh 2017-3-28
Population has two row Position and cost. Lets say I have a population initialized as (Position; Cost) (1 1 1; 3) (2 2 2; 12) (3 3 3; 27)
Say xi = (2 2 2) #Position
As it is in the population then member corresponding to it should be removed from the population. New population should be
(1 1 1; 3) (3 3 3; 27)
KSSV
KSSV 2017-3-28
Pos = reshape([P.Position] ,3,[])' ;
[val,idx] = ismember(xi,Pos,'rows') ;
pick = setdiff(1:length(P),idx) ;
iwant = P(pick) ;
Atinesh Singh
Atinesh Singh 2017-3-28
is there any other way to do it
KSSV
KSSV 2017-3-28
Define xi as a structure..And try using ismemeber etc.

请先登录，再进行评论。

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Structures 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by