How do I assign multiple variables the array data from multiple rows in a field

2023 3 15
1 个回答
回答已采纳
更新时间：2023 3 15
16 次查看（30 天）

0 个投票

I am new to MATLAB programming and am having trouble even asking the right question. I am trying to assign 6 variables the array data from 6 vertical cells (rows), from a field called "analysis.opt_history.error". When I type this:
A = analysis.opt_history.error
I get the array from the first row (this is OK):
A =
1.068 0.749 0.749 0.737 0.737
However, I also want to retrieve the array data that is in Rows 2 through 6 and assign the values of each cell to B, C, D, E, F separately. I cannot figure out how to do this despite much time reading the community. Thanks!
Mark

请先登录，再回答此问题。

 采纳的回答

Matt J
Matt J 2023-3-15
编辑：Matt J 2023-3-15
Ran in:

1 个投票

Ran in:
Is this what you mean?
data={1,2,3,4,5,6}'
data = 6×1 cell array
{[1]} {[2]} {[3]} {[4]} {[5]} {[6]}
[A,B,C,D,E,F]=deal(data{:})
A = 1
B = 2
C = 3
D = 4
E = 5
F = 6

5 个评论
显示 3更早的评论 隐藏 3更早的评论

Mark Sloan
Mark Sloan 2023-3-15
Yes, this is what I am trying to do, but when I applied it to my data it still did not work. I've attached a screenshot of the workspace structure I am trying to get the data from and put into the 6 variables (Field = "error" with 6 rows). This is what I typed in:
[A,B,C,D,E,F]=deal(analysis.opt_history.error{:})
This is MATLAB's response:
"Expected one output from a curly brace or dot indexing expression, but there were 6 results."
From the attached screenshot, here is what I am trying to get (this defines success):
A = 1.0680 0.7429 0.7429 0.7429 0.7429 0.7429 0.7371 0.7371
B = 0.7910 0.7462 0.7462 0.7462 0.7462 0.7462 0.7428 0.7428
C = 1.5977 0.8013 0.8013 0.8013 0.7783 0.7783 0.7783 0.7783 0.7761
D = 4th row array
E = 5th row array
F = 6th row array
Thank you for your quick response!
Mark
Stephen23
Stephen23 2023-3-15
编辑：Stephen23 2023-3-15
The field ERROR has no cell arrays, so the curly-brace indexing is a red-herring**. In fact, there are no cell arrays anywhere in the data shown in your screenshot, unlike what you explained in your question.
All you need is the dot-indexing to refer to the ERROR field:
[A,B,C,D,E,F] = deal(analysis.opt_history.error)
** as well as being syntatically incorrect when appended after a comma-separated list:
https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them
Mark Sloan
Mark Sloan 2023-3-15
That works! Thank you so much for your quick help! I'll need to study cell arrays (and what is not a cell array). Many thanks!
Matt J
Matt J 2023-3-15
@Mark Sloan You're welcome, but please Accept-click the answer to indicate that it worked.

请先登录，再进行评论。

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Matrix Indexing 的更多信息

产品

版本

R2020a

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by