A way to compute dot product of an array and a vector

58 Ansichten (letzte 30 Tage)
Elina Park
Elina Park am 26 Sep. 2018
Bearbeitet: Torsten am 8 Jul. 2023
Hi, So if I have a 2-D array such as
[1 2
3 4
5 6]
and a vector such as
[7 8]
I want to have matlab calculate the dot product of the rows of the array and the vector, and save the results as a column vector. How can I do this?

Akzeptierte Antwort

Walter Roberson
Walter Roberson am 26 Sep. 2018
[1 2
3 4
5 6] * [7 8].'
  2 Kommentare
Francesco Bernardini
Francesco Bernardini am 8 Jul. 2023
Hi, thank you for the answer, it solved my problem;
however, is the dot before the ' needed?
Usually it means elementwise-operation but here I don't see the connection with the transposition;
Torsten
Torsten am 8 Jul. 2023
Bearbeitet: Torsten am 8 Jul. 2023
.' means: usual transpose
' means: conjugate transpose
If the arrays are all real-valued, both operations give the same result. If they are complex-valued - not.
a = [1 2];
a'
ans = 2×1
1 2
a.'
ans = 2×1
1 2
a = [1 + 1i , 2-3*1i];
a'
ans =
1.0000 - 1.0000i 2.0000 + 3.0000i
a.'
ans =
1.0000 + 1.0000i 2.0000 - 3.0000i

Melden Sie sich an, um zu kommentieren.

Weitere Antworten (0)

Kategorien

Mehr zu Matrix Indexing finden Sie in Help Center und File Exchange

Produkte

Community Treasure Hunt

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

Start Hunting!

Translated by