# Star Strider

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. Time Zone: UTC-7 (Standard); UTC-6 (Daylight Savings/Summer)

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Swapping X and Y Axis of a Figure for a One-layer Matrix

I can’t run your code. Try this — contourf(E.') instead. That will transpose the matrix. so it should display the way y...

8 hours ago | 0

Generate a time series from power spectral density

In that event, just create a sine curve of the appropriate frequency or frequencies as determined by the PSD result. This will ...

12 hours ago | 0

Trying to find the integral under the curve at a certain bandwidth

Try this — clear all close all clc L=10; n=1.45; c=2.9979e8; dt = 6e-12; T=10*2*L*n/c; t = (-T/2/dt:1:T/2/dt)*dt; N...

16 hours ago | 0

Prepare Fourier Amplitude Spectrum from ground motion record (Peak-Acceleration vs time-period)

Perhaps this — T1 = readtable('india.19911019...at_output.txt'); T1.Properties.VariableNames = {'Peak Acceleration','Time'} ...

21 hours ago | 0

Other ways to improve fft amplitude

Another option may be to zero-pad the fft using: Fs = signal_sampling_frequency L = signal_length; NFFT = 2^nextpow2(L) FTs...

21 hours ago | 1

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How can I write a set of first order ODEs with two variables?

Try something like this — syms D g m t x(t) y(t) Y dx = diff(x); d2x = diff(dx); dy = diff(y); d2y = diff(dy); DEqn1 ...

1 day ago | 1

Recover signal from single-sided spectrum using ifft

The problem appears (to me) that you are using the absolute value (‘P2’) of the fft result. This essentially discards the phase...

2 days ago | 0

FFT to a simple sine wave

I am not certain what the independent variable axis is (the label is cut off), however if you want a power spectral density plot...

3 days ago | 0

I am recieving an error in creating the solution however it still prints a result.

In the last iteration of the loop, the results are all empty. One way to avoid the error is to test for at least one field to ...

4 days ago | 0

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Solving ODE using laplace

Your code looks correct to me, and when I checked the result with dsolve, its solution agreees with yours — syms t s y(t) Y X ...

4 days ago | 0

Old Matlab example of 1D FFT filter

The only function that I am aware of that might do what you want is the fftfilt function (introduced before R2006a). It require...

5 days ago | 0

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Plot a vector with a given angle against the y-axis

Another approach — thetad = 280; % Desired Angle (Guessing Value) x...

5 days ago | 0

Decreasing bin size FFT options for increased resolution

You can minimise the spectral leakage by windowing the fft (except for a rectangular window, which is the default if no others a...

6 days ago | 0

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Could anyone explain the example provided in thr help for understanding the use of fft?

This calculation of the frequency vector for the displayed Fourier transform is not the easiest to understand: f = Fs*(0:(L/2)...

7 days ago | 0

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Need help in assigning frequency and normalising amplitude to the fft plot

There may be several approaches to your problem. One of them is this — clear all close all clc L=10; n=1.45; c=2.9979e...

7 days ago | 0

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Left and Right side have different elements

You need to subscript ‘t’. Then, it works — t = 0:0.01:4; % Timesteps for robotic arm motion for i = 1:length(t...

8 days ago | 0

Error using Odearguments - vector must return a column

You only have one differential equation, so only one initial condition is necessary. %r_H2= -(-Rds - Rwf - Rh); %Rd = kds*(C...

8 days ago | 0

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I want to change the symbolic variables in my matrix to numbers

Use the fplot function — clear all ; close all; close ; clear syms s Expr = (sin(s)); F1 = int(Expr) syms n expr2 = 1/n ...

8 days ago | 0

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How to remove (or isolate) side peaks except main peak after FFT

Using: NFFT = 2^nextpow2(numel(signal)) and a window function (for example hann) in the fft call could improve the fft result...

8 days ago | 0

Trying to combine two IR spectra where x is wavenumber (cm-1) and y is transmittance (0 to 1), having trouble.

It would help to have the data. The best way is probably to interpolate the longer series to the length of the shorter series...

9 days ago | 0

Tornado chart with colormap gradient

Perhaps something like this — % Data data = [0.496; % Electrical conversion efficiency 0.426; % Biogas efficiency val...

9 days ago | 0

I'm trying to find displacement from acceleration datas

Your original ac celeration data have a trend, and you are integrating the trend. Use the detrend function tto remove it (alter...

9 days ago | 0

Fitting an anonymous function: Debye Callaway Model

I do not have your data so I cannot run your code. However it is always appropriate to compltely vectorise objective function...

9 days ago | 0

How to Reshape a Matrix into a Cell

Transpose the row vector, call reshape, then transpose that result — syms R11 R12 R13 R21 R22 R23 R31 R32 R33 k = 1; timest...

10 days ago | 0

Curve fit autocatalytic model

if ‘x’ is greater than 1 and ‘n’ is not an integer, the result will be complex. Example — k = rand m = rand n = rand x ...

10 days ago | 0

fsolve function not solving nonlinear equations, I had observed "Invalid datatype. Options argument must be created with OPTIMOPTIONS"; could you assist me, pse

One problem is that fsolve wants the initial parameter estimates as a single vector, and the third argument is the ‘options’ str...

10 days ago | 0

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apply hanning window for signal processing

I do not understand your code, so I am not certain where to suggest adding the hann call in that context. (I specifically do no...

10 days ago | 0

How to assign new variables?

Use the strrep function instead of the if block — jj = 1; dependent_vars{jj} = 'act_per_ha'; jj = 2; dependent_vars{jj} = ...

12 days ago | 0

Latex, sprintf and variable that changes

Your sprintf statement has fields for 3 variables, however you only provide 2. Provide all 3 and it works — i = 1; j = 1; ...

12 days ago | 0

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Why I have the error Genetic algorithm script error no Global Optimization Toolbox ?

You have to license, download and install the Global Optimization Toolbox. There is no separate license for gamultobj. You m...

12 days ago | 0