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From: Dan on 5 Apr 2010 12:48
Hi,
I know how to create an array of zeros i.e. if i type a=zeros(1,4) then a=0 0 0 0
however i've totally forgotten how to create an array with curly brackets, i.e. i want to create a={0,0,0,0} which is a=[0] [0] [0] [0] but i want to specify the amount of zeros i want.
Any help would be appreciated,
Thanks
From: us on 5 Apr 2010 13:03
"Dan " <drcscott(a)hotmail.co.uk> wrote in message <hpd484$hkc$1(a)fred.mathworks.com>...
> Hi,
> I know how to create an array of zeros i.e. if i type a=zeros(1,4) then a=0 0 0 0
> however i've totally forgotten how to create an array with curly brackets, i.e. i want to create a={0,0,0,0} which is a=[0] [0] [0] [0] but i want to specify the amount of zeros i want.
> Any help would be appreciated,
> Thanks

one of the very many solutions

a(1:4)={0}
% a = [0] [0] [0] [0]

us
From: Jan Simon on 5 Apr 2010 15:28
Dear Dan!

Or:
a = cell(1, 4);
a(:) = {0};

Jan
From: Bruno Luong on 5 Apr 2010 16:00
Some ways that I could think of (restrict to not using for-loop)

%%
a{1,4}=0;
a(:)={0}

%%
a=cell(1,4);
a(:)={0}

%%
a(1:4)={0}

%%
[a{1:4}]=deal(0)

%%
a={0};
a=a(ones(1,4))

%%
a=repmat({0},1,4)

%%
a=num2cell(zeros(1,4))

%%
a=mat2cell(zeros(1,4),1,ones(1,4))

%%
a=arrayfun(@(x) {x}, zeros(1,4))

% Bruno
From: James Tursa on 5 Apr 2010 16:48
"Bruno Luong" <b.luong(a)fogale.findmycountry> wrote in message <hpdfga$emf$1(a)fred.mathworks.com>...
>
> %%
> a=num2cell(zeros(1,4))
>
> %%
> a=mat2cell(zeros(1,4),1,ones(1,4))
>
> %%
> a=arrayfun(@(x) {x}, zeros(1,4))

I would point out to OP that the last three methods listed by Bruno above do not share the 0 array among the elements like the other methods do, so I would not recommend them if you extend the method to much larger sized cell arrays. Better to use one of the other methods that uses shared arrays.

I would also point out to OP that if you are doing this to preallocate the cell array with the intent to replace them later then don't bother. Once you do a{__} = something assignment then the 0 cell gets wiped from memory anyway. Best to just use the cell( ) function to create a desired size cell array with a bunch of NULL pointer cell elements and then fill them up later with your code. But if you are actually using the 0 value somewhere later in your code then pre-filling with 0 makes sense.

James Tursa
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