Answered

z transform of a left handed sequence

Hi AlireaA You are on the right track by breaking this problem into two parts. Let's look at the first part syms n integer sy...

z transform of a left handed sequence

Hi AlireaA You are on the right track by breaking this problem into two parts. Let's look at the first part syms n integer sy...

16 dagar ago | 0

| accepted

Answered

z transfer function evaluates to inaccurate value near z=1

Hi Ashish, This problem illustrates a couple of things to keep in mind when using the Control System Toolbox Here is the origi...

z transfer function evaluates to inaccurate value near z=1

Hi Ashish, This problem illustrates a couple of things to keep in mind when using the Control System Toolbox Here is the origi...

16 dagar ago | 2

Answered

Failing to plot a fourier transform

Hi Lorenzo, On the face of it, the Symbolic Math Toolbox treatment of (normalized) sinc(x) is disappointing. Perhaps there are ...

Failing to plot a fourier transform

Hi Lorenzo, On the face of it, the Symbolic Math Toolbox treatment of (normalized) sinc(x) is disappointing. Perhaps there are ...

16 dagar ago | 1

| accepted

Answered

Infinity appears at Constant block in Simulink

That “inf” is the sample time of the constant block. As is the “D1” on the other blocks. Check the Simulink doc on sample times ...

Infinity appears at Constant block in Simulink

That “inf” is the sample time of the constant block. As is the “D1” on the other blocks. Check the Simulink doc on sample times ...

18 dagar ago | 0

| accepted

Answered

How to apply the reference target for LQR or LQG controller

Hi JS, One common way to track a reference input with a Type 1 system is to use integral control by augmenting the plant with a...

How to apply the reference target for LQR or LQG controller

Hi JS, One common way to track a reference input with a Type 1 system is to use integral control by augmenting the plant with a...

29 dagar ago | 1

| accepted

Answered

Why am I receiving three outputs for this lsim function?

Hi Hunter k1=1; A=[0 1 0 0 ;-k1 -0.4 k1 0.4 ;0 0 0 1; 0.25 0.1 -0.25 -1.35]; B=[5;0;0;0]; C=[1 0 0 0]; D=0; x0 = C; t = 0...

Why am I receiving three outputs for this lsim function?

Hi Hunter k1=1; A=[0 1 0 0 ;-k1 -0.4 k1 0.4 ;0 0 0 1; 0.25 0.1 -0.25 -1.35]; B=[5;0;0;0]; C=[1 0 0 0]; D=0; x0 = C; t = 0...

30 dagar ago | 0

Answered

Solve differential equation to get variable

Hi Milan, I modified as follows. Not sure if this is what you're looking for: syms d_F ; syms d_F_c; syms dM_B; %syms Thet...

Solve differential equation to get variable

Hi Milan, I modified as follows. Not sure if this is what you're looking for: syms d_F ; syms d_F_c; syms dM_B; %syms Thet...

ungefär en månad ago | 0

| accepted

Answered

How to fix errors within double integral.

Hi @Amanda, The doc page for integral2 say that the function that defines the integrand "must accept two arrays of the same siz...

How to fix errors within double integral.

Hi @Amanda, The doc page for integral2 say that the function that defines the integrand "must accept two arrays of the same siz...

ungefär en månad ago | 0

| accepted

Answered

Having trouble with nonpolynomial equation systems

Equations 1, 2, 5, and 6 can be solved for a parametric solution under some (I hope) reasonable asumptions on the variables. I c...

Having trouble with nonpolynomial equation systems

Equations 1, 2, 5, and 6 can be solved for a parametric solution under some (I hope) reasonable asumptions on the variables. I c...

ungefär en månad ago | 0

Answered

Signal dimensions inside a simulink function

Based on the error message, it sounds like you'e requried to specify the dimensions of that outport. Do you know what the dimens...

Signal dimensions inside a simulink function

Based on the error message, it sounds like you'e requried to specify the dimensions of that outport. Do you know what the dimens...

ungefär en månad ago | 0

Answered

Can anyone help understand what the blocks in this figure are and where to find them in Simulink library?

Assuming these are both from Simulink library. 1. Double click on the block. The BlockType will be at the top of the resultsing...

Can anyone help understand what the blocks in this figure are and where to find them in Simulink library?

Assuming these are both from Simulink library. 1. Double click on the block. The BlockType will be at the top of the resultsing...

ungefär en månad ago | 0

Answered

location of second peaks in fft

Hi peter, The elements of the output of fft as implemented in Matlab correspond to angles around the unit circle. For an N-poin...

location of second peaks in fft

Hi peter, The elements of the output of fft as implemented in Matlab correspond to angles around the unit circle. For an N-poin...

ungefär en månad ago | 0

| accepted

Answered

integral of two added function can't be implemented

Hi Faisal, If the plot for the answer to Q4 is corret, then does the integration really need to start from -inf? However, I su...

integral of two added function can't be implemented

Hi Faisal, If the plot for the answer to Q4 is corret, then does the integration really need to start from -inf? However, I su...

ungefär en månad ago | 0

Answered

Symbolic dependency apparently sometimes gives wrong answers

Hi Mohammad, This works, at least for the examples cited in this comment. Haven't tested for anything but those examples. syms...

Symbolic dependency apparently sometimes gives wrong answers

Hi Mohammad, This works, at least for the examples cited in this comment. Haven't tested for anything but those examples. syms...

ungefär en månad ago | 0

Answered

how to find the area between sinx and sin2x with plot on range [0,pi] as from this code its giving negative area,?

Hi Aashay, After commenting out the code for pos and negArea that wouldn't run because y is not defined (and even if was define...

how to find the area between sinx and sin2x with plot on range [0,pi] as from this code its giving negative area,?

Hi Aashay, After commenting out the code for pos and negArea that wouldn't run because y is not defined (and even if was define...

ungefär en månad ago | 0

| accepted

Question

Should ztrans Work Better when Using heaviside() ?

Recently ran across peculiar behavior with ztrans. Define some variables syms n integer syms T positive Set sympref so that ...

ungefär en månad ago | 0 answers | 0

Answered

how to make a sum of squares symbollically known to MATLAB for use in simplification

Hi Michael, simplify works for this case: syms a b c d x y z f = (a) * (b) * (c) * (1- x^2 - y^2 - z^2) * (d) assume(1 - x^...

how to make a sum of squares symbollically known to MATLAB for use in simplification

Hi Michael, simplify works for this case: syms a b c d x y z f = (a) * (b) * (c) * (1- x^2 - y^2 - z^2) * (d) assume(1 - x^...

ungefär en månad ago | 0

Answered

eigenvalue diagonalization in matlab

Does eig not provide the solution, assuming a solution exists?

eigenvalue diagonalization in matlab

Does eig not provide the solution, assuming a solution exists?

ungefär en månad ago | 0

Answered

Measure Phase/Gain Margin from a different phase reference using margin()?

Hi Alex, I'd look at the problem as follows syms s T0 = sym(-97.74e3); % T0, the DC loop transmission f0 = sym(5); %...

Measure Phase/Gain Margin from a different phase reference using margin()?

Hi Alex, I'd look at the problem as follows syms s T0 = sym(-97.74e3); % T0, the DC loop transmission f0 = sym(5); %...

ungefär en månad ago | 0

| accepted

Answered

How to get max of repeated values?

Can use splitapply C = [0.5000 0.5000 0.3000 1.0000 0.8000 0.3000 0.7000 0.7000 0.3000 0.4000 ...

How to get max of repeated values?

Can use splitapply C = [0.5000 0.5000 0.3000 1.0000 0.8000 0.3000 0.7000 0.7000 0.3000 0.4000 ...

ungefär en månad ago | 0

Answered

Getting Simulink compile-time error "Grid inputs must be vectors or the output of MESHGRID" even though I don't get that error when I try testing those lines in MATLAB

That's an odd error message insofar as interpn actually requires the the grid inputs to be the output of NDGRID (not MESHGRID) a...

Getting Simulink compile-time error "Grid inputs must be vectors or the output of MESHGRID" even though I don't get that error when I try testing those lines in MATLAB

That's an odd error message insofar as interpn actually requires the the grid inputs to be the output of NDGRID (not MESHGRID) a...

ungefär en månad ago | 0

Answered

How to output a vector in MATLAB Function in Simulink?

One problem that I should have seen before is that this line [xdot_3,xdot_4] = Minv * [same stuff here]; should be temp = M_t...

How to output a vector in MATLAB Function in Simulink?

One problem that I should have seen before is that this line [xdot_3,xdot_4] = Minv * [same stuff here]; should be temp = M_t...

ungefär en månad ago | 0

Answered

string extraction from a table

Age = [38;43;38;40;49;45;42;24;50;99]; Smoker = logical([1;0;1;0;1;1;1;0;0;1]); LastName = {'Brown_Howard';'Johnson';'Lee';'Di...

string extraction from a table

Age = [38;43;38;40;49;45;42;24;50;99]; Smoker = logical([1;0;1;0;1;1;1;0;0;1]); LastName = {'Brown_Howard';'Johnson';'Lee';'Di...

ungefär en månad ago | 0

| accepted

Question

Are Arithmetic Operations on a Cell Array of sym Objects Documented Behavior?

I inadvertently stumbled across this behavior: syms z H(z) = 1/(z+1) - 1/(z+2) c = children(H(z)) whos c c is a cell array ...

ungefär en månad ago | 0 answers | 2

Answered

Simulink signal is double when it should be logical.

Hi Sam, Set the initial condition of the Delay block (or Unit Delay block, not sure which is being used) to false or true as de...

Simulink signal is double when it should be logical.

Hi Sam, Set the initial condition of the Delay block (or Unit Delay block, not sure which is being used) to false or true as de...

ungefär en månad ago | 0

| accepted

Answered

Displaying sum on plot

Use text rng(100) x = rand(10,1); % some data plot(x) text(1,.1,"Sum = " + string(sum(x))) Modify as needed

Displaying sum on plot

Use text rng(100) x = rand(10,1); % some data plot(x) text(1,.1,"Sum = " + string(sum(x))) Modify as needed

ungefär en månad ago | 0

| accepted

Answered

Graphing Fourier magnitude and phase spectra using fft, error: Array indices must be positive integers or logical values.

Hi Luke, At the line in question, we see that x(t) is non-integer numeric value, which can't be used to index into the array ff...

Graphing Fourier magnitude and phase spectra using fft, error: Array indices must be positive integers or logical values.

Hi Luke, At the line in question, we see that x(t) is non-integer numeric value, which can't be used to index into the array ff...

ungefär en månad ago | 0

Answered

matrix math problems , error in matrix size

Hard to say without without knowing anything about the data in the question. Based on the wording it should work as follows A =...

matrix math problems , error in matrix size

Hard to say without without knowing anything about the data in the question. Based on the wording it should work as follows A =...

ungefär en månad ago | 0

| accepted

Answered

Creating a Closed loop transfer function of a model

Hi Jacob, Perhaps a clue is that the code doesn't use loop1 after it's computed. Once you have loop1, how does it relate to G2 ...

Creating a Closed loop transfer function of a model

Hi Jacob, Perhaps a clue is that the code doesn't use loop1 after it's computed. Once you have loop1, how does it relate to G2 ...

ungefär en månad ago | 0

| accepted

Answered

How to solve a non-linear system of differential equations?

Hi Pacao, The missing step is a call to odeToVectorField before the call to matlabFunction. Check that first doc page and then ...

How to solve a non-linear system of differential equations?

Hi Pacao, The missing step is a call to odeToVectorField before the call to matlabFunction. Check that first doc page and then ...

ungefär en månad ago | 0