# 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

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Number of line for fcontour

A somewhat different approach — syms x y z(x,y) = exp(-(x-5)^2) + cos(y) figure hfc = fcontour(z, [0 10 -2*pi 2*pi]);...

ungefär 9 timmar ago | 0

| accepted

ho to find index at which the 50% of the sum vector is included?

A least-squared-difference approach works — a=[3 5 7 3 5 8 9 3 1 41 6]; suma = cumsum(a); suma50 = suma(end)/2; [minv,idxv]...

ungefär 11 timmar ago | 1

How can I skip the first to lines from a text file and proceed to read the file with header lines in between the values?

Try this — C1 = readcell('https://www.mathworks.com/matlabcentral/answers/uploaded_files/814274/BSH_HBM_tracer_productgrid_f...

ungefär 17 timmar ago | 0

How to activate the low-pass filter on NI-6115?

It will likely be best to Contact Support for this. I did an online search and could find no previous posts regarding the NI-61...

ungefär 20 timmar ago | 0

| accepted

Function value and YDATA sizes are not equal. Can anyone help?

The problem is the randn call. With one argument, it creates an (nxn) matrix, not a vector, so of course the sizes will not mat...

ungefär 21 timmar ago | 1

Error with the division

Use the table2array function to convert the contents of the table to an array. Assign the arrays to new variables rather than o...

ungefär 21 timmar ago | 0

error [empty sym] using dsolve "Warning: unable to find symbolic solution"

It is likely not possible to derive a closed-form (analytic or symbolic) solution for those. Create an anonymous function to us...

en dag ago | 0

How to define values in a vector as NaN ?

Try this (using ismember) — A = [1 2 3; 4 5 6]; B = [2 3; 5 6]; C = ismember(A,B) A(C) = NaN .

en dag ago | 1

| accepted

Define an additional variable in ODE solver

This is all a bit confusing, since the differential equations are not them selves functions of ‘C1’ and ‘C2’, so a differential ...

en dag ago | 0

Can't Uninstall, What Should I Do?

Option #1: Contact Support The uninstall function deletes registry entries as well, however a fresh install should over-write...

en dag ago | 0

symbolic variables into double array, observability matrix

The variable values need to be provided in order to use the Control System Toolbox funcitons. To do this symbolically, create...

en dag ago | 0

How can I estimate the parameter of reaction kinetics using ODE solver?

I am not absolutely certain how to approach this because chemical engineering is not an area of my expertise. First, I would ...

en dag ago | 0

Question in continuous time signals

Everything in a computer are discrete, not continuous (except the voltages on the chips themselves and the outputs of a soundcar...

2 dagar ago | 0

How to solve the implicit equation

First, a multiplication operator (my best guess, anyway) is missing: ((alfa*Vt*Vmpp*(2*Impp-Isc))/((Vmpp*Isc+Voc*(Impp-Isc))*(...

2 dagar ago | 0

How can we combine the two figures?

‘When you execute the code below, two plots are drawn.’ No, not without knowing what the variables are. However the prob...

2 dagar ago | 0

Calculate this matrix in a more general and shorter way

Yes, actually. However since it appears that the objective is to do a Fourier transform, I would set it up a bit differently ...

2 dagar ago | 0

ODE45/ODE15 inquiry about nonlinear spring

Since the system appears to describe a differential-algebraic equation, see the documentation section on Solve Differential Alge...

2 dagar ago | 0

Symbiological output using 'syms' and 'pretty' commands

Experiment with the indexing into the expressions (since this is a straightforward solution to a number of otherwise difficult p...

2 dagar ago | 0

How do I reflex a plot?

Try this — u = -8:1:1.3; v = -pi:pi/10:pi; for k = 1:numel(v) x{k,1} = 1 + u + exp(u)*cos(v(k)); y{k,1} = v(k) +...

2 dagar ago | 0

how to increase function values through its derivetive

Do some simple experiments to see what produces the desired result — syms k x dx1 = 2*x; ...

3 dagar ago | 0

Problem to solve integration

Change this — f = @x sin(x); to this — f = @(x) sin(x); That should work. .

3 dagar ago | 0

Removing a particular legend from plot

The first two lines have the same line style. To see them individually, choose a different line style for each. To label t...

3 dagar ago | 0

| accepted

how to solve the following equation?

Try this — a=[1,2,3]; afcn = @(b) ((b-2).*(b+1))./((b+3).*(b-1)); [estb,fval] = fminsearch(@(b) norm(afcn(b) - a), rand) ...

3 dagar ago | 0

| accepted

How to plot 3D filled contour ?

It would help to know the data and the desired result. One option is to use the surf function and contour3 — [X,Y,Z] = peak...

3 dagar ago | 0

Using ode45 for a non linear differential equation with a term in a vector form

I do not understand the problem. Is the objective to estimate a parameters of the differential equation from data? The tim...

3 dagar ago | 0

| accepted

why do I get an error "First input argument must be a function handle"

I have no idea what the code does. See if this paproximates the desired result — nUn = 2000; nU2n = 1500; nU3n = 200;...

3 dagar ago | 1

I need help solving RC circuit using Leplace inverse, then graph the output which is in the symsum form

Sometimes a bit fo force (such as using vpa) is necessary — syms s t Ys2(s)=((2*s^2+7*s+3)/(2*s^3+11*s^2+15*s+4)*(2*s+2)/(...

4 dagar ago | 1

| accepted

2D contour plot with given matrix

Two possibilities — M = [25, 25, 25 111.5, 137.8, 245.1 146.3, 178.3, 296.4 111.5, 137.8, 245.1 25, 25, 25]; figure ...

4 dagar ago | 0

| accepted

from curve fit to look up table

The question is a bit ambiguous. Interpolation of some sort would appear to be the best option, and of course the approach de...

4 dagar ago | 0

Curve fitting for multivariable

There are several options. I’m using fminsearch here. xdata = ... [0.882263937 0.882263937 0.882263937 0.882263937 0...

4 dagar ago | 0

| accepted