StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PO
primarykey
Id
9795692
data
AcceptedAnswerId
0
AnswerCount
0
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2012-03-20T22:02:28.593
FavoriteCount
0
LastActivityDate
2012-03-20T22:20:41.063
LastEditDate
2012-03-20T22:20:41.063
LastEditorUserId
1157224
OwnerUserId
1157224
ParentId
9794555
PostTypeId
2
Score
2
ViewCount
0
LastEditorDisplayName
text
Body
The short answer is this: <pre><code> A(sub2ind(size(A),X,Y)) = V </code></pre> Try it out, it works like a charm. The explanation, if you're curious and want it, is simple to follow: Every matrix in Matlab is stored as a 1d array, a normal vector. A 2d array is actually stored in memory as a sequence of the first column, followed by the second column, and so on. Because of that, you can index any Matlab array, independent of its dimension, by a linear subscript. For example: <pre><code> A = [1 4 7; 2 4 8; 3 6 9 ]; </code></pre> Is actually stored as: <pre><code>[1 2 3 4 5 6 7 8 9] </code></pre> So to access item all you have to do is: (j-1)*num_of_columns + i Because of that, A(2,3) returns the same as A(8), that is, in this case: 8; The sub2ind function transforms a list of "subscripts" to linear indexes, given the size of the matrix. Exactly what you want to do. And with the indexes at hand, it is easy to make the assignment. Docs: <a href="http://www.mathworks.com/help/techdoc/ref/sub2ind.html" rel="nofollow">sub2ind</a> <a href="http://www.mathworks.com/help/techdoc/math/f1-85462.html" rel="nofollow">Indexing in Matlab</a> Hope I understood you correctly. I took the time to answer in a long fashion because this is a very important part of Matlab, and a LOT of people overcomplicate the code using the "vector-operating" functions to do things that could be done with normal indexing.
Tags
Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POhow to assign a set of coordinates in Matlab?
 singulars
 PostTypePostTypeId
 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. USCastilho
UserOwnerUserId
1. USCastilho
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. POhow to assign a set of coordinates in Matlab?
 singulars
 PostTypePostTypeId
 PTQuestion
PostsParentIdCreationDate
1. This table or related slice is empty.
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTAcceptedByOriginator
2. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
CommentsPostId
1. This table or related slice is empty.

Querying!

Guidance

A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.