Communities

Writing
Writing
Codidact Meta
Codidact Meta
The Great Outdoors
The Great Outdoors
Photography & Video
Photography & Video
Scientific Speculation
Scientific Speculation
Cooking
Cooking
Electrical Engineering
Electrical Engineering
Judaism
Judaism
Languages & Linguistics
Languages & Linguistics
Software Development
Software Development
Mathematics
Mathematics
Christianity
Christianity
Code Golf
Code Golf
Music
Music
Physics
Physics
Linux Systems
Linux Systems
Power Users
Power Users
Tabletop RPGs
Tabletop RPGs

Dashboard
Notifications
Mark all as read
Q&A

What does variable in sup represent for matrix?

+1
−0

I had seen people were representing matrix 2 way.

  1. $$\sum_{j=1}^n a_{ij}$$

It is representing a column matrix (vector actually) if we assume $i=1$.

$$\begin{bmatrix}a_{11} & a_{12} & a_{13} & ......\end{bmatrix}$$

  1. $$\sum_{j=1}^n a^{ij}$$

What it is representing? At first I thought it was row matrix (vector) since it is opposite of column matrix (vector). But when I was writing the question I couldn't generate a row matrix using the 2nd equation. I confuse more when I see $a_j^{i}$ sometimes there's two variable in sub and sup. $a_{ji}^{kl}$ I don't remember if one of them matches (I meant I am not sure if I write it wrong way).

Why does this post require moderator attention?
You might want to add some details to your flag.
Why should this post be closed?

1 comment thread

Needs more context (2 comments)

0 answers

Sign up to answer this question »

This community is part of the Codidact network. We have other communities too — take a look!

You can also join us in chat!

Want to advertise this community? Use our templates!

Like what we're doing? Support us! Donate