# logarithmically spaced vector in a certain range

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Nuchto on 3 Oct 2014
Commented: Johann Martinez on 15 Mar 2021
How to create a logarithmically spaced vector say from values 3 to 10? Thank you!

Azzi Abdelmalek on 3 Oct 2014
Edited: Azzi Abdelmalek on 3 Oct 2014
pas=0.1
t=log(3):pas:log(10)
out=exp(t)
%or
n=10 % number of samples
out=exp(linspace(log(3),log(10),n))
Azzi Abdelmalek on 3 Oct 2014
n=10 % number of samples
out=log(linspace(exp(3),exp(10),n))
Nuchto on 3 Oct 2014
Thank you!

Nathan Porter on 7 Apr 2017
Like Marco, I would suggest using logspace. For example,
logspace(1,3,10)
creates a vector of 10 logarithmically spaced values between 10^1 and 10^3. If you instead want the bounds to be determined by a value and not the exponent, I generally use the following:
logspace(log10(3),log10(10),10)
This will create a vector of 10 logarithmically spaced values between 3 and 10.
Johann Martinez on 15 Mar 2021
Thank Nathan, but what if I have a, b values equals to 0, 0.97, for example?
I mean, the logspaced vector is full of NaN, because of the negative logarithm...

Marco on 3 Oct 2014
To my knwoledge you could just use the built-in command logspace.