# Single value to multiple fields

## Cell arrays

set all cells to 'A'

s=cell(1,5);

s{:}='A'

ERROR: The right hand side of this assignment has too few values to satisfy the left hand side.

a) using the command deal to expand 'A' to the number we need.

[s{:}]=deal('A')

b) converting string 'A' to a cell {'A'} that is mapped to all selected cells(:) of s

s(:)={'A'}

'A' 'A' 'A' 'A' 'A'

Example: replace all 'C' with 'A'

s = {'C','B','C','B','C'};

idx = ismember(s,'C');

s(idx)={'A'}

'A' 'B' 'A' 'B' 'A'

## Struct array

set multiple fields of a struct array

[ s(10:20).field ] = deal( 'A' )

Example

% create struct array

for i=1:5

end

'A' 'A' 'A' 'A' 'A'

a) using deal()

[ Metadata(3:end).group ] = deal( 'C' ) ;

b) using cell array to modify values

group = { Metadata(:).group }; % struct array to cell array

group(2)={'B'};

group(3:end)={'C'};

[ Metadata.group ] = group{:}; % copy back to struct-array

% check values in struct-array

'A' 'B' 'C' 'C' 'C'

## Numerical matrices

set all values smaller than 0.5 to zero

x = rand(2,4)

0.8641 0.4547 0.7844 0.9137

0.3889 0.2467 0.8828 0.5583

idx = x<0.5

x(idx)=0

0.8641 0 0.7844 0.9137

0 0 0.8828 0.5583

http://www.mathworks.com/help/matlab/ref/deal.html

https://mathworks.com/help/matlab/ref/cell2struct.html