David Hill

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3,466 total contributions since 2017

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Answered
Could someone explain this straight line function?
It is point-slope form of a line. If the points are a=[x2, y2] and b=[x1, y1], then: m=(a(2)-b(2))/(a(1)-b(1));%slope func =@(...

1 day ago | 0

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How can I move the bars in a bar chart?
figure; bar_displacement=.25;%play with this until it is correct bar(x-bar_displacement,y); set(gca,'XTick', x);

3 days ago | 0

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ignore NaN values in loop
CC=[]; for i = 2:16 A = walknov(:,i); A = interpft(A(~isnan(A)), 100); if isempty(A) CC=[CC;nan(1,100)]; ...

3 days ago | 0

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using for loop plotting problem help me
What are you trying to plot? f= @(x) 3*x.^5+7*sin(x).^2;%I doubt you want sind fd= @(x) 15*x.^4+7*sin(2*x).^2+3*x.^5+7*sin(x)...

4 days ago | 0

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Conditional statements on array.
i=reshape(Input,12,[])'>100; Output=zeros(size(i)); for k=1:size(i,1) if nnz(i(k,:))>0 Output(k,:)=1; end ...

4 days ago | 1

Answered
what it does mean?
If the matrix 'index' indexed at (1,1) equals 1, then assign S1 =0 and S2 = 0. if index(1,1)==1 S1=0; S2=1; end

4 days ago | 0

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for loop issue not all answer printing out
function T = InterestPayment(P,r) for n=1:10 A(n) = P*((r*(1+r)^n)/((1+r)^n-1)); end T= table ((1:10)',A', 'VariableN...

4 days ago | 0

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How can I find the nonzero values in an cells array?.
Non_ceros=zeros(length(Index)); for i = 1 : length(Index) for j = 1 : length(Index) Non_ceros(i,j) = nnz(In...

4 days ago | 0

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Answered
wanna creat a matrix of unknowns and write some equations with those unknowns and then take the matrix of coefficients
syms a b c d; t=[a b;c d]; coef=[2 3]; eqn=dot(coef,t(1,:));

4 days ago | 0

Answered
for loop help - Newton's method
I would avoid symbolic unless you need to. f = [2,-6,-12,20,42,18]; df = polyder(f); tol=1e-10; error=1; x=[-2,4];%initial ...

4 days ago | 0

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Answered
store user input in an array
user_input= zeros(1,10); for i = 1:10 while user_input(i)<=0 user_input(i) = input('Enter positive real number : '); ...

4 days ago | 0

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How to convert binary bits of a vector, say m, after rotating it left by 1 bit, into decimal ?
m = [16; 10]; %use column vector a = fi(m, 0, 8, 0); b = bin(bitrol(a, 1)); c = bin2dec(b);

5 days ago | 0

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Answered
Generate random numbers in the second decimal point
x=1.198:0.1:2.198; x=x-(randi(6,size(x))+3)/100;

8 days ago | 1

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How to optimize the calculation of the mean between the elements of A and B efficiently?
C=(A+B)/2;

10 days ago | 0

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DOE points normal distrbution
m=standard_deviation.*randn(1,1000)+mean;%generates an array of 1000 numbers

11 days ago | 0

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Finding an unknown vector from three known vectors
syms x y z; C=[x,y,z]; A = [125 350 -80]; B = [-115 350 -80]; D = [-15 530 545]; eq1=norm(A-C)==300; eq2=norm(B-C)==300;...

11 days ago | 0

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Answered
Unable to concatenate the table variables 'Var1' and 'Var2', because their types are double and cell.
Why not just readmatrix? What column are you skipping? p = readmatrix('Arrone-pluviometro(36045)-2019-0-24'); p(isnan(p))=9999...

12 days ago | 0

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Integrate definite integral with system of differential equations
Can you just do something like this? function dydt = odefun(t, y, c) dydt(1,:) = 1./(1+t.^2) ; % h(t) h=@(x)1./(1+x.^2); ...

12 days ago | 0

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Answered
How can I implement a loop to find the minimum among 5 values
Are you not allowed to use the min() function? function D = myfun(A) D=min([.1 3 5 8 12]./cumprod(A));

12 days ago | 0

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Using fzero on function
y=@(x)x.^6-2.*cos(x); x=linspace(-3,3,100); plot(x,y(x)); z(1)=fzero(y,-1); z(2)=fzero(y,1);

12 days ago | 0

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Answered
How to Define a Symbolic Continued Fraction
function L = continuedFraction(N,n) syms A B; if n==0 L=0; else L=1/(B/(N-1)+A/N+continuedFraction(N,n-1)); end R...

13 days ago | 1

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FSOLVE with For loop
Not sure what values you what for b, but you will not to do a surf plot or plot3 (3d plot) f=@(x,b)x.^3.*b+exp(-b.^2)+x.*b-500;...

13 days ago | 0

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Issue with creating a plot from two for loops
a=1.63279*10^-6; b=264.9889; T=373:10:1273; Mu = (a*T.^0.5)./(1+b./T); n = 0.666; T0 = 273; Mu0 = 1.375*10^-5; MuT = Mu0....

13 days ago | 1

Solved

Replace secondary diagonal elements of a square array
Replace all the secondary diagonal elements of the square array A with the number n Example: A = [1 2 3 4 5 6 ...

22 days ago

Solved

Compound interest - number e
A moneylender wants to receive his annual interest of 12% more frequently. If he receives his interest rate every six months,...

22 days ago

Solved

Double the next and alternate sign

22 days ago

Solved

Find the slope

22 days ago

Solved

Potential energy calculation

22 days ago

Solved

Total energy