Community Profile

# Star Strider

##### Last seen: Today
13,273 total contributions 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.

View details...

Contributions in
View by

Genetic algorithm plot diagram display
It is generally necessary to write your own code to save specific aspects of the ga output. It may be best to adapt the code ...

1 hour ago | 0

How to delete a whole table in the matlab?
tablename = [];

2 hours ago | 1

| accepted

How can I separate the arrays when making a table?
Try this: n = 5; A = rand(n,1); B = rand(n,5); T = array2table([A, B]) That should do what you want.

2 hours ago | 1

| accepted

how to combine date and time
In theory at least, datetime should be able to do this seamlessly using the timeofday function for the seconds. In practice, it...

8 hours ago | 0

What am I doing wrong? Matrix operators
If you want to raaise the elements of a matrix to a power, use element-wise exponentiation with the dot operator: .^ and see: Ar...

11 hours ago | 0

how to use fir1 for highpass filter with window
See the fir1 documentation section on window. Specifically: ‘The window vector must have n + 1 elements.’ So ‘n+1’ should ...

11 hours ago | 0

I can't plot a function I created with respect for time
You need to code it as an anonymous function. See Anonymous Functions for details. Specifically: x = @(t) X.*(exp(-Zeta.*...

23 hours ago | 0

Error when solving system of equations with ode45 in MATLAB R2019b
The system contains only two derivatives, and . It appears that ‘u’ and ‘z’ are either functions that need to be evaluated, or...

1 day ago | 0

How to plot a function that relies on another function?
Since ‘A’ is a function, it must be evaluated in order to use its results. Try this: A = @(y) y*2; X = @(y) A(y)+10; f...

1 day ago | 0

| accepted

How to make this signal linear
If you want to eliminate the low-frequency parabolic(?) trend, the easiest way is to use a digital filter: signal_2 = load('si...

2 days ago | 0

| accepted

I'm trying to understand your tables command bugs
Both of these work for me: A = randi([0 20],5, 5); Atable1 = array2table(A, 'RowNames',{'a' 'b' 'c' 'd' 'e'},'VariableNames',...

3 days ago | 0

Designing IIR Butterworth filter (pass band)
Yes. Just define the order as 5. There are different design functions in the Signal Processing Toolbox (butter that I have a...

3 days ago | 0

Play 2 wav files after each other
Use the playblocking function to get them to play the way you want them. [y1, Fs1] = audioread('file1.wav'); %this file i...

3 days ago | 1

I have a function which is ranged from 0 microseconds to 50 microseconds. I just want to plot its exact copies from 0to50 microsecond,50 to 100microseconds,100 to 150 and so on
Try this: Ts=1/200e6; t=Ts:Ts:0.00005; y=[ones(1,2000) zeros(1,8000)]; x=sin(1256e6*t + 2198e10*t.^2); z=x.^y; NR = ...

3 days ago | 0

How to condense a plot with a shorter x-axis?
Divide the x-axis vector by max(x), assuming ‘x’ is the x-axis vector. That will re-scale it without losing any information.

4 days ago | 0

How to avoid a for loop in functions?
Use ‘logical indexing’ and anonymous functions to eliminate the for loop and the if block: PsolWB1 = @(press) (973.-(70400./(1...

4 days ago | 0

| accepted

fsolve for non linear equation
One problem is that you called fsolve inside the function. That is not appropriate. The other is that you use global variables...

4 days ago | 0

power law fit to find exponent
I would do this (no Toolboxes required): x = linspace(0, 5, 50); % Create Data y = x.^pi ...

4 days ago | 0

Definite integral without symbolic variables
Create ‘fun’ as an anonymous function, then use the integral function: fun = @(z) (G1 + G2 - 2*cos(k*L1/2) * G0) .* sin(k*(L2/...

4 days ago | 0

kinetic energy of the wind (u and v vectors)
Apparently, ‘h’, ‘u’, and ‘v’ are vectors of the same dimensions. One approach is to code the function as an anonymous functi...

4 days ago | 0

| accepted

how to plot euler formula in matlab?
The plot function plots lines between points. You have only one point, so if you change the plot call to: y = exp(100*i*pi) ...

4 days ago | 0

| accepted

The dot operator, used with multiplication, division, and exponentiation, creates element-wise oiperations. See Array vs. Matri...

5 days ago | 1

| accepted

How to sort the rows of an array according to another vector?
Try this: D=[1 1 0 1 0 1; 4 6 7 8 9 9; 1 1 1 2 3 4]; b=[2 44 0]; [bb,idx] = sort(b,'descend'); Out = D(idx,:) producing: ...

5 days ago | 0

| accepted

How to change the values in a matrix
One approach: Before = [ 1 9 9 9 3 8 9 9 9 4 8 9 9 9 ...

5 days ago | 0

| accepted

Inverse of algebraic expression in Matlab
Possibly: rfcn = @(E) fsolve(@(r) 1-1/2*((1+r).*log2(1+r)+(1-r).*log2(1-r)) - E, 10); % Anonymous Function: r(E) N = 200;...

5 days ago | 0

| accepted

Designing an Arbitrary FIR Filter
This is probably as close as you can get: Frequency = [100 125 160 200 250 315 400 500 630 800 1000 1250 1600 200...

5 days ago | 1

| accepted

Plot the Intensity and phase of variation of electric field.
The Fourier transform is easy enough to calculate and plot: t = dlmread('t_spectrum_11480.txt','',1,0); E = dlmread('y_spectr...

5 days ago | 0

| accepted

How to fix axes in dynamic plot
Try this: x=@(t)(sin(4*t)).^2; y=@(t)cos(5*t); z=pi; figure(1) for t=0:0.002:z plot(x(t),y(t),'.','MarkerSize',4,'c...

6 days ago | 0

| accepted

How can plot this curve in matlab ?
This appears to approximate it: k = linspace(0,1); Finesse = 5./k; figure plot(k, Finesse)

6 days ago | 0

| accepted