Community Profile

# Star Strider

Last seen: Today Active since 2012

Hic sunt dracones!

PROFESSIONAL: Physician (M.D.): Diplomate of the American Board of Internal Medicine; M.Sc. Biomedical Engineering: Instrumentation, Signal Processing, Control, System Identification, Parameter Estimation

NON-PROFESSIONAL: Amateur Extra Class Amateur Radio Operator; Private Pilot, Airplane Single Engine Land, Instrument Rating Airplane; Gamer

NOTE: I do not respond to emails or personal messages, unless they are about my File Exchange contributions.

All

#### Content Feed

View by

smoothdata function not working for matrix . any one have ideas to what is going on?
Try this — LD = load('mat.mat'); a = LD.a; for k = 1:size(a,2) a_smoothed(:,k) = smoothdata(a(:,k)); end x = 1:si...

alrededor de 4 horas ago | 0

problem with fit function for data
The fit function requires column vector arguments. Force that sith the ‘(:)’ subscript noitation. E = [416.861, 818.7, 109...

alrededor de 7 horas ago | 0

How to use one marker for looped plots in legend
I cannot run the posted code, however the solution may be straightforward. figure hold on for k = 1:50 hs{1} = scatter...

alrededor de 11 horas ago | 0

fit 2nd order differential equation parameters to data
The problem appears to be not allowing the intial conditions to be estimated as parameters as well as the initial value of ‘a_m’...

alrededor de 11 horas ago | 0

| accepted

Using solve to find intersection points
It’s as simple as it looks — syms x f(x) = exp(-x^2) g(x) = sym(0.8) xi = solve(f == g) xi_vpa = vpa(xi) .

alrededor de 14 horas ago | 0

| accepted

How can I simplify the folllowing equation
One approach — syms x Eqn = 2*x^2 - 2*x*(2*x^2 - 1) + 2*x*(2*x*(2*x^2 - 1) - 2*x^2 + 1) - 1 Eqn = simplify(Eqn, 500) .

1 día ago | 0

| accepted

How to plot data with two different X- axis in a single plot?

1 día ago | 0

translating and solving an equation with values of x and y known
In the third term, the square root is of the numerator only, not the entire expression, amd the denominator does not appear to h...

1 día ago | 0

To determine whether the system is stable.
Welcome to the wonderful world of floating-point approximation error! See ‘Check’ and ‘Check_max’ for an illustration of the ...

2 días ago | 1

| accepted

How to properly format a data table with fprintf?
In the numeric edit descriptors, the value to the left of the decimal is the field width (this includes all the numbers, the sig...

2 días ago | 0

Find which matrix row contains average minimum value
One approach — M = rand(288,365); AMV = mean(min(M)) % Average Minimum Value [val,idx] ...

2 días ago | 0

| accepted

trying to find theta
The Question lacks clarity. % plot mountain Mn_x = [0, 1000, 3014.8]; Mn_y = [0, 0, 616]; plot (Mn_x, Mn_y) hol...

2 días ago | 0

| accepted

Solve for x given y and plot
Depending on what you wan, either use fzero or interp1 — y = @(x) (2 * exp((2*x)/3)) - ((7*x.*exp((2*x)/3))/3); x = linspace(...

2 días ago | 0

| accepted

Doubt in solving ODE45
It seems that ‘dis’ does not appear anywhere. L=20; v=20;%v (m/sec) T=L/v; tspan_1=[0:0.001:T];%time range y0_1=[0;0];...

3 días ago | 0

How do you plot a line of constant value on a surface plot?
See if contour3 or contour3m will do what you want. [X,Y,Z] = peaks(30); figure surf(X,Y,Z) hold on contour3(X,Y,Z,[1 1...

3 días ago | 0

How to properly create function for integration?
There are several problems with the posted code image. First, ‘z’ is not defined anywhere, and it is not an argument to ‘E_fu...

3 días ago | 0

How can I plot the derivatives of the components of the solution to a system of ODEs?
The only way is to use al loop — tspan = [0 50]; z0=[0.01 0.01 0.01 0.01]; [t,z] = ode45(@(t,z) coupled(t,z), tspan, z0); ...

3 días ago | 2

| accepted

Cannot calculate integral function
If you want a numeric result, use vpaintegral (introduced in R2016b) instead of int. Not all expressions have analytic integral...

3 días ago | 0

| accepted

How to convert logarithmic to linear
If you have the Signal Processing Toolbox, use the db2mag function. If you do not have it: dB2mag = @(dB) 10.^(dB/20); ...

3 días ago | 0

Matlab Polar Plot Legend does not match with the plot
I cannot run that and I amm not certain what you are are plotting. Create a handle for each polarplot call: th = linspace(0, ...

3 días ago | 0

How to save output of double loop as a matrix?
Since ‘A’ is a matrix, save it as a cell array — for i=1:m for j=1:n A{i,j} = myfunction(...) end end .

4 días ago | 1

| accepted

There are NaN values in ‘x’, ‘y’, and ‘sd’. This ia frequent cause of patch failures. Remove them and it works! Try this ...

4 días ago | 1

| accepted

3D Sphere projection in Matlab
I worked on this for a while yesterday, without success. Today, I used a relatively straightforward approach that simply flips ...

4 días ago | 1

How would I go about writing this equation in matlabs?
There are several options, depending on what you want to do. syms x p(x) = 1/(2*sqrt(sym(pi)))*exp(-(x-5)^2/4) figure f...

4 días ago | 0

| accepted

How to save .mat file into hdf5 in matlab?
I have no recent experience with HDF5 files, however the h5write documentation for data indicates that it must be a numeric matr...

4 días ago | 0

Error with plotting my function
It works if you give ‘f’ a vector to work with — f = @(x) 2.^x-5*x+2; %Given Function xaxis = [0:0.5:2]; ...

4 días ago | 2

| accepted

I am trying to plot an ellipse using a polarplot function.
The polarplot function requires the angular measure to be in radians. Change that in the polarplot call and it works. (The e...

4 días ago | 0

| accepted

Am I using corrcoef correctly?
‘Am I using corrcoef correctly?’ Yes, except for squaring the result, and that will produce . H=log([0.01 0.02 0.03 0.04 ...

5 días ago | 0

| accepted

Converting a linear equation to decibel
The ‘theta’ vector likely needs to have more points, however that appears to be correct. I use a slightly different approach ...

5 días ago | 0

| accepted