What is the difference between .' and ' when transposing a matrix?

I am new to MatLab, and when I try to transpose a matrix , it seems that using .' and ' produce the same effect. For matrix a, for example, I can do

a.'
a'

and they produce the same result. Is there a difference between these two?

Answer 1

[Star Strider]

They produce the same result only for real values. The ‘regular’ transpose operator (') produces a complex-conjugate transpose for complex numbers. With the dot operator (.') it produces the transpose without performing the complex-conjugate operation.

Note: This is the only operation (that I am aware of) where the dot-operator does not signify element-wise operations, as it does with multiplication, division, and exponentiation.

[Ron Fredericks]

Thank you Star Strider.

For scalar, vector, matrix with complex numbers:

transpose(A) and A.' produce nonconjugate transpose of A

ctranspose(A) and A' produce complex conjugate transpose of A (a.k.a. Hermitian transpose)

For real number scalar, vector, matrix both methods are equivalent

Answer 2

[Geoff Hayes]

Tianyi - according to MATLAB operators and special characters,

 .' performs a matrix transpose
  ' performs a complex conjugate transpose

And so you would only notice a difference if your a is complex (or an array of complex elements).

Answer 3

[dpb]

doc punct  % Concise description of all Matlab punctuation-symbols syntax

doc transpose
doc ctranspose

for the two specific operators. (It's certainly a pit(proverbial)a(ppendage) for newcomers that neither of

help .'
doc .'

return the information requested. One would think TMW would have fixed that in 40 yr or so... :(

In general I suggest starting with the "Getting Started" tutorial lessons at

doc

and work your way through the early portions--it'll make the entry much faster if you do than if not...