what is the meaning of A(:,:,1:2:3);

X = [];
temp = A;
if B > 0
  while temp <= C
    X = [X, temp];
    temp = temp + B;
  end
elseif B < 0
  while temp >= C
    X = [X, temp];
    temp = temp + B;
  end
end

In the case of 1:2:3, with positive increment, you check whether 3 is less than 1, and since it is not less than your result will have at least one result in it. Start with the 1 in the list. Add the increment, 2, to that value. The result, 3, is not greater than the end point (3), so add the result to the list, so the list is [1 3] now. Add the increment 2 to that last value, getting 5. 5 is greater than the end point of 3, so stop. The list is finished.

Another way of saying this is: the numbers starting at 1, and no more than 3, that are 2 apart from each other. 1 and 3 satisfy that so they are both included.

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Jan 2017-6-20

+1 for the last sentence, which is a rare case of English being leaner and more clear then Matlab.

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Answer 2

YOGESH RAMESH 2020-9-5

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https://ww2.mathworks.cn/matlabcentral/answers/345453-what-is-the-meaning-of-a-1-2-3#answer_490183

B(1:2,3)

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Walter Roberson 2020-9-8

在 MATLAB Online 中打开

As examined above, 1:2:3 is the list of numbers that includes 1 and 3. You would then index B at locations 1 and 3. Linear indexing would be used, so if B were 2 x 4