Adding a new field to a struct array

1,268 次查看（过去 30 天）
C Delog
C Delog 2018-1-26
评论： Walter Roberson 2022-6-11
Hey All! I'm trying to add a new field to a struct array inline. I have the following struct:
A(1).name = 'bob';
A(2).name = 'cindy';
newstruct = 'address'
How do I go about adding the a field A.address to the array struct with the field name being define din the newstruct variable? The existing array should then look like the following:
A(1).name = 'bob';
A(2).name = 'cindy';
A(1).address = [];
A(2).address = [];

请先登录，再回答此问题。

采纳的回答

Walter Roberson
Walter Roberson 2018-1-27
A(1).(newstruct) = value;
If you have a cell array of contents to be put into existing entries, then you can use
[A.(newstruct)] = values_cell{:};
to set all of them at the same time.
  2 个评论
sarah wentzel
sarah wentzel 2022-1-23
what are value in the first option and values_cell in the second? are those new variables?
Walter Roberson
Walter Roberson 2022-6-11
value in the above could be any variable or expression of any size or data type.
values_cell in the above would have to be a variable containing a cell array, in which the number of entries was the same as numel(A); each cell entry could be any data type or size.
More obscurely, values_cell could instead be the name of a true function (not function handle) for a function that could be called with no parameters, and which returned a cell array.
More obscurely still, values_cell could be the name of a class with a class constructor that could be invoked with no parameters, and the class defined subsref with {} operation, or defined the specialized method for overloading {}, so that the class name with no parameters defines an object and the {:} invoked whatever the {} operation was redefined as.

请先登录，再进行评论。

更多回答（2 个）

Kallam Haranadha Reddy 
A(1).name = 'bob';
A(2).name = 'cindy';
A(1).address = ' Flat No.502, Apple Towers,...
 1st line, Ravindra Nagar, Guntur,Andhra Pradesh, India,PIN-522006';
A(2).address = ' Flat No.102, Balaji Towers,...
2nd line, Brodipet, Guntur, Andhra Pradesh, India, PIN-522006';
sarah wentzel
sarah wentzel 2022-1-23
编辑：sarah wentzel 2022-1-23
I created this cell
somecell = struct('Name', {'bob', 'lea', 'pat'}, 'Birth_year', {1990, 1988, 2021})
and now I want to add new information, favorite color. I know I can do it one by one like this:
somecell(1).color = 'blue'
somecell(2).color = 'red'
somecell(3).color = 'green'
But is there a way to do it with only one line? something like;
somecell (:,3).color = {'blue', 'red', 'green'}
thank you!
  1 个评论
Stephen23
Stephen23 2022-1-23
编辑：Stephen23 2022-1-23
Ran in:
S = struct('Name', {'bob', 'lea', 'pat'}, 'Birth_year', {1990, 1988, 2021})
S = 1×3 struct array with fields:
Name Birth_year
[S.color] = deal('blue','red','green')
S = 1×3 struct array with fields:
Name Birth_year color
Or from a cell array:
C = {'small', 'large', 'medium'};
[S.tshirtsize] = C{:}
S = 1×3 struct array with fields:
Name Birth_year color tshirtsize
https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html
https://www.mathworks.com/matlabcentral/answers/320713-how-to-operate-on-comma-separated-lists

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Data Types 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