Community Profile

photo

Craig Cowled


Last seen: 2 months ago

Queensland University of Technology

28 total contributions since 2011

Contact

Craig Cowled's Badges

  • First Review
  • 3 Month Streak
  • Thankful Level 2
  • Knowledgeable Level 2
  • First Answer

View details...

Contributions in
View by

Question


importfile regexp thousands separator returns NaN when negative
I used "Import Data" to generate a function importfile for importing a csv file. Unfortunately, the function returns NaN for ev...

2 years ago | 1 answer | 0

1

answer

Answered
Is it possible to make a manual Nyquist plot using polar(theta,rho)
Jeffrey, I usually keep my data in one complex vector rather than having two vectors (i.e., mag & phase). Then it's a simple th...

8 years ago | 0

Question


how to pass multiple values of x to objective function in GA / Patternsearch
I'm looking for ways to speed up the computation of my optimisation process. I've already used the PROFILE command to pinpoint ...

8 years ago | 1 answer | 0

1

answer

Answered
Genetic Algorithm options 'PopInitRange' not working
Alan, thank you for such a good explanation. Cleared it up for me nicely.

8 years ago | 0

Question


Genetic Algorithm options 'PopInitRange' not working
I am using GAOPTIMSET to establish an upper and lower bound for my initial population in a GA optimisation. I have abbreviate...

8 years ago | 2 answers | 0

2

answers

Answered
How do you share a variable from another function to be used in a different function?
Cordelle, I'm not going to re-write your code for you, but I will suggest that you read up on nested functions, here ... ht...

8 years ago | 0

| accepted

Answered
power spectrum VS amplitude of FFT function
Power = 20 * log10(abs(FFT))

8 years ago | 0

Answered
Restarting Genetic Algorithm after Crash
Many thanks yet again, Alan. Will write a little function to handle the crash and restart the GA. As for patternsearch, I mi...

8 years ago | 0

Answered
Matlab crashes when calling dll
Try using 'loadlibrary'.

8 years ago | 0

Question


Restarting Genetic Algorithm after Crash
I'm using the GA to update my Finite Element Model. The fitness function I am using is computationally expensive and takes 4sec...

8 years ago | 2 answers | 0

2

answers

Answered
Use of PSD functions to obtain FRFs
I thought I should tie up a loose end with this question. I discovered that the data acquisition from my impact hammer was faul...

8 years ago | 1

Answered
Curve fitting a complex function using cftool
MattJ, not sceptical ... always worthwhile to know the intrinsic quirks of an algorithm. I used your code and compared the di...

8 years ago | 0

Answered
Curve fitting problem and strange message
Fei, if the "change in residuals is less than tolerance" then this is an indication that you have a reasonably good fit. I ha...

8 years ago | 0

Answered
genetic algorithm error not enough input arguments
Hey, what do you know, it worked!! Btw, your recommendation of using LSQNONLIN was the right call too. Although the GA wor...

8 years ago | 0

Answered
genetic algorithm error not enough input arguments
Alan, Thank you for taking the time to answer this in so much detail! Point taken regarding the choice of optimization too...

8 years ago | 0

Question


genetic algorithm error not enough input arguments
function deltaH = curvefit_H_2modes(w1,w2,m1,m2,c1,c2) load('file.mat'); z = -(x.^2) .* ((1 ./ ((w1.^2 * m1) -...

8 years ago | 4 answers | 0

4

answers

Answered
How to Fix this Error!
Send this to Matlab Support. Obviously their help file has the wrong code.

8 years ago | 0

Answered
RMS question plss help me
Mohd, if you have the Signal Processing Toolbox, you can use the _rms_ function like this: X = [0.234 0.2338 0.255 3.456 5....

8 years ago | 0

Answered
Curve fitting a complex function using cftool
I just noticed another question on the forum in which someone suggested to use _mldivide_. I'll have a look at this when I get ...

8 years ago | 0

Answered
how to acces and change value inside transfer function inside a loop
Kobi, I tried running your code and got an error message. It looks like you missed a space between G.den{1,1} and (k) in the li...

8 years ago | 0

| accepted

Answered
pseudorandomise vectors in an array
Doug, I use a function that was developed by Jos, called _allcomb_. You can find it at the following link <http://www.mathworks...

8 years ago | 0

| accepted

Answered
How can I generate random numbers with constraints?
I think you have actually answered your own question. If x = randi([3 18], 7); gives you a 7 x 7 matrix of random numbers betwe...

8 years ago | 0

Question


bar3 width depend on zdata?
Ok, so I know how to make the colours on my bar graph depend on zdata .. h = bar3(data); for ii = 1:length(h) zdata =...

8 years ago | 0 answers | 0

0

answers

Answered
Boxplot with time on x axis
Found the answer ... Need to use 'positions' like this boxplot(Y,'positions',X)

8 years ago | 4

| accepted

Answered
Excel Date Format to Matlab Number Array
Have you tried using datevec? Take one of the cells as an example ... '02/03/2013'. >> datevec('02/03/2013','mm/dd/yyyy')...

8 years ago | 0

| accepted

Question


Boxplot with time on x axis
Does anybody know how to obtain a boxplot with time on the x axis? I have collected experimental observations at irregular in...

8 years ago | 1 answer | 1

1

answer

Question


Curve fitting a complex function using cftool
I'm using the cftool toolbox to find fits for a complex valued transfer function. The toolbox clearly can't handle a complex nu...

8 years ago | 3 answers | 0

3

answers

Question


Use of PSD functions to obtain FRFs
Hi, I am doing some modal analysis on a steel structure and have encountered some troubling issues while using Matlab's Power...

9 years ago | 2 answers | 1

2

answers