Community Profile

# James Tursa

##### Last seen: Today
3,384 total contributions since 2007

Interested in external applications, mex & engine applications with Fortran, C, C++, etc, particularly in the areas of speed improvement and memory management efficiencies.

View details...

Contributions in
View by

arrange an array(1xn) to (rxc)
Not sure how you want the output ordered. Maybe this A = reshape(m,9,9); or this A = reshape(m,9,9).';

3 hours ago | 0

while loop ends before the question is answered?
Your break is in the wrong place. It should be under one of the if conditions: if user_number==r disp('Nice job you gue...

3 hours ago | 0

Extra independent component in ode integration affects other components
The integrators do not internally step each element separately. They still step the entire state vector as a whole. So even tho...

4 hours ago | 0

| accepted

ODE 45 not working - not enough input arguments
ode45( ) requires that the derivative function handle have the specific arguments (t,y), where y is a single state vector. But y...

4 hours ago | 0

| accepted

ode45 - nonscalar
I suppose you could do something like this instead: F{1} = etc. F{2} = etc. F = F'; f = @(X,T)cell2mat(cellfun(@(c)c(X,T),F,...

5 hours ago | 0

Column Vector - Nonscalar arrays.
F = @(X, T) [F1(X, T); F2(X, T)];

6 hours ago | 1

How to find an explicit function when using Runge-Kutta or one of the pertinent codes in Matlab (ode45)
Symbolic Toolbox doc dsolve https://www.mathworks.com/help/symbolic/dsolve.html

6 hours ago | 0

Extracting parts of matrix for sub matrices
E.g., to put them into a cell array mat = your matrix result = mat2cell(mat,repmat(16,8,1),repmat(16,8,1));

6 hours ago | 0

Exact probability of a triangular distribution
The exact probability of getting a number greater than the mean is simply the sum of the probabily to the right of the mean. Si...

7 hours ago | 1

| accepted

I want to rotate a point using Quaternion function
I took a look at this related link: https://github.com/petercorke/robotics-toolbox-matlab/blob/master/Octave/%40Quaternion/Quat...

9 hours ago | 0

Converting sensor frames using Aerospace Toolbox

10 hours ago | 0

Problems with sortrows and str2double, why is it still string?
>> [~,x] = sort(str2double(Respiration_Values)); >> B = Respiration_Labelled(x,:) B = 7×2 string array "139299" "...

10 hours ago | 1

Binary Image: Count number of pixels that are 1.
nnz(bw)

1 day ago | 1

error when running a function
Do not push the green triangle "go" button in the editor since that calls the function without any input arguments. Instead, cal...

1 day ago | 1

solving a set of differential equations with ode45
Initial conditions is a 4-element vector: IC1=[0; 0; 298; 298]; But in your derivative function you have this: M=[5,15,25,55]...

1 day ago | 0

| accepted

Loops - physics - nonlinear gravity & acceleration
Your immediate problem is that h is a vector, so the right hand side of this statement is a vector: g(i+1)=(400000000/(6371+h...

1 day ago | 0

Looping over column and returning values where conditions are met
In general, perform find( ) on the condition you want. E.g., find(matrix(:,4)>80) would return the row numbers where the 4th c...

2 days ago | 0

sparse half-precision matrices
The sparse format in MATLAB only supports double and logical data types. To use any other data type you would have to write all...

2 days ago | 0

| accepted

RK4/AB4, need help with correct code for 2 second order equations in Matlab
So, first define a 4-element state vector. To keep the nomenclature the same as the MATLAB docs, I will use the variable name y....

2 days ago | 0

Cell Arrays and Indexing?
This is the reverse of your last assignment. It needs only one loop over the number of rows, and the cell array element for tha...

3 days ago | 0

| accepted

Cell arrays and Indexing with Cells HELP?
This row = Q(1:end); col = Q{1:end}; Z(row, col) = true; is actually a good attempt and shows you understand the problem .....

3 days ago | 0

| accepted

repeat the iteration with an error using try/catch
Maybe this construct does what you want while( true ) try MyProgramHere ...

3 days ago | 0

Storing doubles in the smallest integer class for which they fit without changing their value?
Some hints: Don't use loops, use vectorized code to figure out which integer size works. intmax(type) gives you the largest va...

3 days ago | 0

| accepted

How do I make a function work with vectors?
Use element-wise divide operator ./ (with the dot) instead of the matrix divide operator / (without the dot). E.g., tanH(x)=((...

4 days ago | 0

| accepted

Your basic problem is that you have two states, x and y, but your function arguments are inconsistent with this. Take this code:...

4 days ago | 1

| accepted

Really! fprintf cell error
What happens if you change this fprintf(fid, '%d %s %s %f',shape{i,:}); to this fprintf(fid, '%d %s %s %f',shape{i,1},shape{i...

4 days ago | 0

| accepted

MATLAB Homework Problem: "Incorrect use of '=' operator" in a for loop
This: for (i = 2:0.5:15 && j = -2:0.5:12) Needs to be two nested loops: for i = 2:0.5:15 for j = -2:0.5:12

4 days ago | 1

Homework help.(User defined functions )
Hint: See these functions: doc size doc isequal doc error

4 days ago | 0

| accepted

trouble understanding for loops
The first problem is getting the input from the user. This assigns a char string to pv: pv=('What was your original mortgage v...

4 days ago | 0