Finding the index of spesific element in a matrix?

조회 수: 726 (최근 30일)
IBM watson
IBM watson 2019년 5월 23일
댓글: Ulika Naidoo 2021년 1월 22일
Lets say we have matrix:
a=[ 2, 3, 5
3, 4, 7
4, 4, 4] ;
I want to know index of a(4) which is the bold 3. This is just an example. I want to learn how to find index of a(n).

채택된 답변

madhan ravi
madhan ravi 2019년 5월 23일
편집: madhan ravi 2019년 5월 23일
Assuming you want to index of the last match in the matrix:
Index=find(a==3,1,'last')
  댓글 수: 13
madhan ravi
madhan ravi 2019년 5월 23일
편집: madhan ravi 2019년 5월 23일
No problem, by the way the original question you asked is totally irrelevant to your latter comment. Please don’t do this in the future riddling the answers.
Look into ind2sub() function to convert the linear indices. To understand what this statement means , you need to read the link which I shared thoroughly and practice. And finally have a look at ind2sub().
IBM watson
IBM watson 2019년 5월 23일
Sure, I didn't do it on purpose. Just could't explain clearly what I want. Thanks again.

댓글을 달려면 로그인하십시오.

추가 답변 (1개)

KALYAN ACHARJYA
KALYAN ACHARJYA 2019년 5월 23일
편집: KALYAN ACHARJYA 2019년 5월 23일
I want to know index of a(4) which is the bold 3
here ......................... this 4^ represent the index, I guessing you are looking for following one.
idx=find(a==3);
One dimentional case array case
>> a=[2,3,5,3,4,7,4,4,4];
>> idx=find(a==7)
idx =
6
>> idx=find(a==3)
idx =
2 4
But Matrices have 2 dimention so indices represents (x,y), where answer will be little different
>> a=magic(3)
a =
8 1 6
3 5 7
4 9 2
>> [r c]=find(a==3)
r =
2
c =
1
  댓글 수: 5
Stephen23
Stephen23 2020년 3월 5일
"why c =1 ? "
Because the value 3 is in the 1st column.
Ulika Naidoo
Ulika Naidoo 2021년 1월 22일
Thank you!

댓글을 달려면 로그인하십시오.

카테고리

Help CenterFile Exchange에서 Matrices and Arrays에 대해 자세히 알아보기

태그

Community Treasure Hunt

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

Start Hunting!

Translated by