Community Profile

# Geoff

2012 年からアクティブ

I use MATLAB for small jobs and C++ for real jobs.
Professional Interests: Problem solving

All

バッジを表示

#### Content Feed

HOW CAN I CALCULATE THE SIGNAL TO NOISE RATIO(SNR) OF A CHIRP SIGNAL
From Wikipedia: http://en.wikipedia.org/wiki/Signal-to-noise_ratio NR = Psignal / Pnoise = (Asignal / Anoise)^2 Where P is powe...

2年以上 前 | 0

| 採用済み

Help with proper parfor
You can't write to a parallel-segmented matrix in the inner loop. Try this: parfor i=1:r col = zeros(n,1); f...

11年以上 前 | 0

| 採用済み

How can I import a .txt file correctly using textscan?
The way to have the most control over a line-based txt file import is to read it one line at a time: while !feof(fid) ...

11年以上 前 | 1

Script adapted into a funtion Function not returning equal values
Floating point precision errors. If you need to test for zero, then test for something like: if abs(value) < 1e-5 10^-5 ...

11年以上 前 | 0

| 採用済み

time to number conversion
From memory, if you use |datenum| to just get the time with no date, it doesn't return a number between 0 and 1. But you can ge...

11年以上 前 | 0

| 採用済み

Do you think that MATLAB is expensive?
Yes, I think it is expensive. In New Zealand, it's about \$2000 per toolbox. The compiler is over \$8000. The work I was doin...

11年以上 前 | 0

Can you use cell or struct as function input？
Yes, and yes. I'm puzzled that you're asking this here when you could quite easily test for yourself... Part of the process ...

11年以上 前 | 3

| 採用済み

Save data from a loop
I think this might be what you want: for f = 1:40 for g = 1:40 i = (f-1) * 40 + g; dpTxcouple1(:,:,i) = ...

11年以上 前 | 0

If it really is about something cool, then I'm in agreement with the others. Go for it... People could still add their own ans...

11年以上 前 | 0

can someone explain this code?
|x1_Y| is an array of indices. You're doing a boolean test on |x1(10:300)| to determine if a point is an outlier. That is, it ...

11年以上 前 | 0

| 採用済み

Need some assistance with "if" command
Oh, the better way is to use the proper MATLAB error function: if a < 0 error( 'Not a valid input.' ); end

11年以上 前 | 0

Need some assistance with "if" command
If you don't have a function or anything to return from, there's a sneaky little trick you can use. This can be useful for othe...

11年以上 前 | 0

| 採用済み

As a Software Engineer, Why should I use MATLAB?
From one developer to another, the answer is: *why not??* What do you have to lose from having another tool (or rather, arsen...

11年以上 前 | 1

frequency

11年以上 前 | 0

| 採用済み

What do I have to do to sort strings properly in Listbox?
Don't ask the same question just because nobody answered it yesterday. If you are impatient, write a comment on it to bump it b...

11年以上 前 | 0

| 採用済み

how to convert Julian date to Gregorian date ?
Use |datestr|

11年以上 前 | 0

| 採用済み

realtime data streaming between matlab and opencv, visual c++
How "realtime" do you need? If you were polling a file multiple times a second, would that be sufficient? Can you do your anal...

11年以上 前 | 0

fprint error
Like the error message says, some of your inputs are structs, and that's not allowed. Run the following code to check the types...

11年以上 前 | 0

What is the purpose of this line in MATLAB's "factorial.m" function?
I would hazard that it is there to handle the special case of computing zero-factorial, which of course is 1.

11年以上 前 | 0

importing csv array of unknown size, characters
So the general thing is this... Keep track of the current state outside the loop: line_num = 0; % Current CSV line number...

11年以上 前 | 1

Non-numeric matrix to string
It's not a matrix. It's a cell array. You can try converting the whole thing to strings with something like: [M{:}] ...

11年以上 前 | 0

| 採用済み

Computer Vision - Feature Detection and Tracking - Tracking a RC car in a video
Of course, but you might have to implement a bunch of complex algorithms yourself. If you're not familiar with vision processin...

11年以上 前 | 0

Find Min& Max Togather
Well, I do it like this: function [Amin, Amax] = minmax( A ) Amin = min(A); Amax = max(A); end Note: Not to...

11年以上 前 | 0

Slightly off topic: determining at the Windows system level when my process is done
Why don't you invoke the shutdown as the last thing your MatLab script does?

11年以上 前 | 1

Matrix to Table format
Are you saying you want to generate the SQL: CREATE TABLE my_table blah blah blah Followed by INSERT INTO my_table ...

11年以上 前 | 0

Combine Two Different Images With Different Gain Values
Here's what I'd do... Convert all your images to 16-bit. Then take the factor-1 image, multiply it by 10. Then take the fac...

11年以上 前 | 1

| 採用済み

Temporal processing of image stack
Well, I'm not known for my solutions that take advantage of inbuilt MatLab functions... Maybe something like |filter| would be ...

11年以上 前 | 0

Financial contract value
Just a snippet of coding advice from me... If you need to use a number more than once, especially if it relates to how many v...

11年以上 前 | 0

Entering data into MATLAB from a csv file containing both data and letters
textscan(currentLine, '%s%s%c%d%d%d%d%f%f')

11年以上 前 | 0

Deleting X-Y points that are not near other points on a field of data points
Naive (brute force) implementation given by per isakson looks sufficient for this problem. O(N^2) is okay for 900 rows. For la...

11年以上 前 | 0