How to replace values in a matrix?

2015 9 21
2 个回答
回答已采纳
更新时间：2015 9 22
1 次查看（30 天）

0 个投票

Hello,
I am fairly new to MATLAB and I have a question. How do you replace a value in a matrix? So if I have a matrix A, where A=3,2,5,-6. How can I find, and replace all of the negative numbers with 0? So I want to end up with a matrix of 3,2,5,0.
Thank you!
Molly

请先登录，再回答此问题。

 采纳的回答

Star Strider
Star Strider 2015-9-21

2 个投票

One way is to use ‘logical indexing’:
A = [3,2,5,-6];
A(A<0) = 0
A =
3 2 5 0

更多回答（1 个）

Molly Baltins
Molly Baltins 2015-9-21

0 个投票

Thank you! This has helped a lot!

5 个评论
显示 3更早的评论 隐藏 3更早的评论

Molly Baltins
Molly Baltins 2015-9-22
I have another question that hopefully you will be able to help with. I have a string and I want to give each letter a character, but I want it to start off with one. So example I have 'Molly' then it will be [1 2 3 4 5]. Thank you!
Star Strider
Star Strider 2015-9-22
My pleasure!
I’m not quite certain what you’re asking, so I’ll take a guess at an answer:
str = 'Molly';
result1 = str(1:5)
result2 = str([3 1 5 2 4])
result1 =
Molly
result2 =
lMyol
I used the colon (:) operator to create the subscript vector in ‘result1’. It is the same as typing [1 2 3 4 5].
Molly Baltins
Molly Baltins 2015-9-22
Perfect! That is exactly what u wanted! Thank you!
Star Strider
Star Strider 2015-9-22
Again, my pleasure!

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Text Analytics Toolbox 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