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Answered

Removing specific rows from a matrix where its corresponding element in another column is zero.

ans = abc; ans(abc(:,3)==0,:) = []

Removing specific rows from a matrix where its corresponding element in another column is zero.

ans = abc; ans(abc(:,3)==0,:) = []

ungefär 3 timmar ago | 0

Answered

plot surface using different x,y vector increment and got different graph

You did not multiply elementwise, also you can shorten your code a little bit: fun = @(x,y) -1.448-0.477*x-0.4757*y+0.1473*x.^2...

plot surface using different x,y vector increment and got different graph

You did not multiply elementwise, also you can shorten your code a little bit: fun = @(x,y) -1.448-0.477*x-0.4757*y+0.1473*x.^2...

ungefär 4 timmar ago | 0

Answered

Is the graph correct for the distance 10km for the okumura model?

There is a publication at FEX which you could use to check your code: https://de.mathworks.com/matlabcentral/fileexchange/28423...

Is the graph correct for the distance 10km for the okumura model?

There is a publication at FEX which you could use to check your code: https://de.mathworks.com/matlabcentral/fileexchange/28423...

ungefär 4 timmar ago | 0

Answered

how to plot a function symbolically?

g = 9.8; r = -10:0.1:10; H = -10:0.1:10; C = -10:0.1:10; fun = @(r,H,C) H - C.^2./(2*g*r.^2); z_r = fun(r,1,1); z_H = ...

how to plot a function symbolically?

g = 9.8; r = -10:0.1:10; H = -10:0.1:10; C = -10:0.1:10; fun = @(r,H,C) H - C.^2./(2*g*r.^2); z_r = fun(r,1,1); z_H = ...

ungefär 4 timmar ago | 0

Answered

why when i plot the graph for the okumura model it doesnt show line?

f is a scalar here - for this reason you have only one data point. Either use scatter to visualize the point or make f an array ...

why when i plot the graph for the okumura model it doesnt show line?

f is a scalar here - for this reason you have only one data point. Either use scatter to visualize the point or make f an array ...

ungefär 5 timmar ago | 0

| accepted

Answered

Unable to convert the text to datetime using the format: 'dd-MM-yyyy hh:mm'

datetime('22-9-2020 10:35','InputFormat','dd-MM-yy HH:mm') datetime('22-9-2020 15:48','InputFormat','dd-MM-yy HH:mm') ans = ...

Unable to convert the text to datetime using the format: 'dd-MM-yyyy hh:mm'

datetime('22-9-2020 10:35','InputFormat','dd-MM-yy HH:mm') datetime('22-9-2020 15:48','InputFormat','dd-MM-yy HH:mm') ans = ...

ungefär 23 timmar ago | 0

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Answered

How do I plot given points using a functions?

x = [1,12,2,6,5] y = [5,23,5,6,3] plot(x,y) % Using a function handle y_fun = @(x) 3.*x + 5; y_vals = y_fun(x); plot(x, ...

How do I plot given points using a functions?

x = [1,12,2,6,5] y = [5,23,5,6,3] plot(x,y) % Using a function handle y_fun = @(x) 3.*x + 5; y_vals = y_fun(x); plot(x, ...

en dag ago | 0

Answered

Solve the equation for x

Make the changes suggested in the answer from KSSV and use vpasolve: syms x p = 0.89; a = 6.7; v = 26.12; r = 0.07; L = 78...

Solve the equation for x

Make the changes suggested in the answer from KSSV and use vpasolve: syms x p = 0.89; a = 6.7; v = 26.12; r = 0.07; L = 78...

en dag ago | 1

Answered

How can I solve this two shaded equations for d1 and d2?

syms d1 d2 Grin eq = [d2 == Grin * d1; (d1+d2) / 2 == 0.15]; sol = solve(eq,[d1,d2]); sol_d1 = sol.d1 sol_d2 = sol.d2

How can I solve this two shaded equations for d1 and d2?

syms d1 d2 Grin eq = [d2 == Grin * d1; (d1+d2) / 2 == 0.15]; sol = solve(eq,[d1,d2]); sol_d1 = sol.d1 sol_d2 = sol.d2

en dag ago | 0

Answered

Alzheimer detection from brain mri image

Have a look at FEX: https://de.mathworks.com/matlabcentral/fileexchange/55107-brain-mri-tumor-detection-and-classification htt...

Alzheimer detection from brain mri image

Have a look at FEX: https://de.mathworks.com/matlabcentral/fileexchange/55107-brain-mri-tumor-detection-and-classification htt...

en dag ago | 0

Answered

how to plot three figures in single figure?

r=[12 23 45 67 77] p=[44 55 66 77 88 ] g=[21 33 23 34 54] k=[55 45 43 23 12] figure plot(r) hold on plot(p) plot(g) plo...

how to plot three figures in single figure?

r=[12 23 45 67 77] p=[44 55 66 77 88 ] g=[21 33 23 34 54] k=[55 45 43 23 12] figure plot(r) hold on plot(p) plot(g) plo...

en dag ago | 1

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Answered

Errors using ode45

%Define PMOIs Ix = 2887; %kg-m^2 Iy = 2887; %kg-m^2 Iz = 5106; %km-m^2 %Define initial conditions x1_0 = 0.6; % OmegaX ...

Errors using ode45

%Define PMOIs Ix = 2887; %kg-m^2 Iy = 2887; %kg-m^2 Iz = 5106; %km-m^2 %Define initial conditions x1_0 = 0.6; % OmegaX ...

en dag ago | 0

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Answered

GA does not solve problems with integer and equality constraints.

Reformulate your constraints: <https://de.mathworks.com/help/gads/mixed-integer-optimization.html#bs1clc2>

GA does not solve problems with integer and equality constraints.

Reformulate your constraints: <https://de.mathworks.com/help/gads/mixed-integer-optimization.html#bs1clc2>

en dag ago | 0

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Answered

Error using sym/subsindex () while using the symsum function

There are two possible ways in Matlab, that allow a syntax like V(k) The first is indexing with a variable like in a for loop:...

Error using sym/subsindex () while using the symsum function

There are two possible ways in Matlab, that allow a syntax like V(k) The first is indexing with a variable like in a for loop:...

en dag ago | 0

Answered

Convert cartesian coordinates to polar coordinates

Edit your file - you did not declare it as a function, so Matlab uses it as a script. Also think about to vectorize your code, t...

Convert cartesian coordinates to polar coordinates

Edit your file - you did not declare it as a function, so Matlab uses it as a script. Also think about to vectorize your code, t...

2 dagar ago | 2

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Answered

Creating a symbolic array

>> q = sym('q', [5, 5]) q = [ q1_1, q1_2, q1_3, q1_4, q1_5] [ q2_1, q2_2, q2_3, q2_4, q2_5] [ q3_1, q3_2, q3_3, q3_4...

Creating a symbolic array

>> q = sym('q', [5, 5]) q = [ q1_1, q1_2, q1_3, q1_4, q1_5] [ q2_1, q2_2, q2_3, q2_4, q2_5] [ q3_1, q3_2, q3_3, q3_4...

2 dagar ago | 0

Answered

I'm getting an error "Undefined function 'Romberg' for input arguments of type 'char'." I'm trying to code the romberg integration method.

For me it worked: a = 0; b = pi; nmax = 3; fun ='sin (x)' ; [t, r]= Romberg (fun, a, b, nmax) function[t , r] = Romberg...

I'm getting an error "Undefined function 'Romberg' for input arguments of type 'char'." I'm trying to code the romberg integration method.

For me it worked: a = 0; b = pi; nmax = 3; fun ='sin (x)' ; [t, r]= Romberg (fun, a, b, nmax) function[t , r] = Romberg...

2 dagar ago | 0

Answered

Is it possible to solve the equation for x?

syms x a(1) = 0.89; a(2) = 6.7; a(3) = 26.12; a(4) = 0.07; a(5) = 78.05; a(6) = 34.01; a(7) = 0.33; a(8) = 22.49; a(9) ...

Is it possible to solve the equation for x?

syms x a(1) = 0.89; a(2) = 6.7; a(3) = 26.12; a(4) = 0.07; a(5) = 78.05; a(6) = 34.01; a(7) = 0.33; a(8) = 22.49; a(9) ...

2 dagar ago | 0

Answered

Fill a vector with two vectors

V1 = [3 8 6 7] V2 = [1 5 9 4] V = reshape([V1;V2],1,[]) V = V(3:end) results in: V1 = 3 8 6 7 V2 =...

Fill a vector with two vectors

V1 = [3 8 6 7] V2 = [1 5 9 4] V = reshape([V1;V2],1,[]) V = V(3:end) results in: V1 = 3 8 6 7 V2 =...

2 dagar ago | 1

Answered

Trying to plot this curve what have I done wrong?

fun = @(x)(18*sqrt(2)*(sqrt(1+1./(1+x.^2)) + asin(1./(1+x.^2)-pi/2))) fplot(fun)

Trying to plot this curve what have I done wrong?

fun = @(x)(18*sqrt(2)*(sqrt(1+1./(1+x.^2)) + asin(1./(1+x.^2)-pi/2))) fplot(fun)

2 dagar ago | 0

Answered

How to find the solution of inverse function ?

x = [1 2 3 4 5 6 7]; y = [3.6 1.8 1.2 0.9 0.72 1.5 0.51429]; p = polyfit(x,y,2) syms x fx(x) = poly2sym(p) gx(x) = finvers...

How to find the solution of inverse function ?

x = [1 2 3 4 5 6 7]; y = [3.6 1.8 1.2 0.9 0.72 1.5 0.51429]; p = polyfit(x,y,2) syms x fx(x) = poly2sym(p) gx(x) = finvers...

2 dagar ago | 0

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Answered

Possible combinations for a vector

You could use allcomb from FEX: k = 0:2; coms = allcomb(k,k,k,k,k,k,k,k,k); as expected there are 3^9 = 19683 results

Possible combinations for a vector

You could use allcomb from FEX: k = 0:2; coms = allcomb(k,k,k,k,k,k,k,k,k); as expected there are 3^9 = 19683 results

2 dagar ago | 1

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Answered

how do i write a matlab script to sum this expression?

Symbolic: syms n positive integer N = 10000; eq = 1/n + 1/((n+2)*(n+3)); pretty(eq) sol = symsum(eq,n,1,N) sol_num = doubl...

how do i write a matlab script to sum this expression?

Symbolic: syms n positive integer N = 10000; eq = 1/n + 1/((n+2)*(n+3)); pretty(eq) sol = symsum(eq,n,1,N) sol_num = doubl...

2 dagar ago | 1

Answered

ODE Function time output

Use events: Z0 = 6; Zt=0.05*6; tspan = [0 24]; opts = odeset('Events',@(tZ,Z)EventsFcn(tZ,Z,Zt)); [tZ,Z,tZe,Ze,iZe] = ode45...

ODE Function time output

Use events: Z0 = 6; Zt=0.05*6; tspan = [0 24]; opts = odeset('Events',@(tZ,Z)EventsFcn(tZ,Z,Zt)); [tZ,Z,tZe,Ze,iZe] = ode45...

3 dagar ago | 0

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Answered

Why isn't my code graph anything.

Try: %create a cater plot clear all; %x = [20,30,40,50] x = [-3,-1,1,2] y = [8,23,28,34] y=[8,23,28,34].' colum = [...

Why isn't my code graph anything.

Try: %create a cater plot clear all; %x = [20,30,40,50] x = [-3,-1,1,2] y = [8,23,28,34] y=[8,23,28,34].' colum = [...

3 dagar ago | 0

Answered

How find symbolic solution matlab

It appears that there either is no symbolic solution or Matlab is not powerful enough to find one. For sin(t) it would work. How...

How find symbolic solution matlab

It appears that there either is no symbolic solution or Matlab is not powerful enough to find one. For sin(t) it would work. How...

3 dagar ago | 1

Answered

ode 45 and for loop

k = 0; T_sol = cell(1,100); X_sol = cell(1,100); for ii = 0.1:0.1:10 k = k+1; [T,X] = ode45(@(t,x)fx(t,x,ii), [0 ...

ode 45 and for loop

k = 0; T_sol = cell(1,100); X_sol = cell(1,100); for ii = 0.1:0.1:10 k = k+1; [T,X] = ode45(@(t,x)fx(t,x,ii), [0 ...

3 dagar ago | 0

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Answered

Graph Plotting the differential equation

yyaxis left fplot(qSol,[0, 100]) yyaxis right fplot(TSol,[0, 100])

Graph Plotting the differential equation

yyaxis left fplot(qSol,[0, 100]) yyaxis right fplot(TSol,[0, 100])

3 dagar ago | 1

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Answered

Defining function file of ODE function

C0 = 5; tspan = [0 10]; [t,C] = ode45(@Conc,tspan,C0); plot(t,C) function dCdt=Conc(t,C) k1=0.7; Vo=1; Q=Vo; Cin=200; ...

Defining function file of ODE function

C0 = 5; tspan = [0 10]; [t,C] = ode45(@Conc,tspan,C0); plot(t,C) function dCdt=Conc(t,C) k1=0.7; Vo=1; Q=Vo; Cin=200; ...

3 dagar ago | 1

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Answered

How do i plot this quadratic graph?

x = -10:10; y = polyval([1 -2 -4],x); plot(x,y) r = roots([1 -2 -4]) text(r(1),0,'\leftarrow Root') text(r(2),0,'\leftarrow...

How do i plot this quadratic graph?

x = -10:10; y = polyval([1 -2 -4],x); plot(x,y) r = roots([1 -2 -4]) text(r(1),0,'\leftarrow Root') text(r(2),0,'\leftarrow...

3 dagar ago | 0