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deal is a good function for such an assignment:
[bins{1:5}] = deal([]);
This creates a cell array bins, where each element bins{i} contains an empty array.
MATLAB only has matrices, i.e. (potentially multidimensional) arrays of numerical types (or characters or logical values). To group other structures in one variable, try a cell array, e.g.
bins = { []; []; []; []; [] };
You then have to access elements of the outer array with curly brackets, e.g. bins{2} instead of bins(2).
Use the [] operator. Example:
x = [];
If you wanna be specific in the type of the empty matrix, use the empty property. Examples:
emptyDoubleMatrix = double.empty; % Same as emptyDoubleMatrix = [];
emptySingleMatrix = single.empty;
emptyUnsignedInt8Matrix = uint8.empty;
This works for empty matrices of classes as well. Example:
emptyFunctionHandleMatrix = function_handle.empty;
You can use the empty matrix/vector notation, [], and Matlab will set up a placeholder for it.
x = []
Now if you want to append a scalar, say num, to it, you cannot index it because it is empty.
However, you can either:
Use array concatenation to concatenate itself with another scalar:
x = [x num]Use the
end+1notation, to address the first available location:x(end+1) = num
Both of the above two notations also work when you want to append a row or a column vector to an existing row vector or column vectors. But when you are concatenating vectors/matrices, remember to be consistent with the dimensions.