The document contains code snippets for three different matrix calculations: 1. Calculating the Euclidean norm of a matrix A by taking the square root of the sum of squares of its elements. 2. Triangularizing a matrix A and updating a corresponding vector B using Gaussian elimination. 3. Calculating coefficients for polynomial interpolation by summing terms involving input vectors X and Y.

1. NORMA EUCLIDIANA
n = length(A)
k=0;
norma = 1;
for i=1:n
for j=1:n
k = k + (A(i,j))^2;
end
alpha = sqrt(k);
norma = norma*alpha;
end
disp('norma euclidiana =')
disp(norma)
TRIANGULARIZACAO MATRIZ A E VETOR B RESULTANTE para Eliminacao de Gauss
n = length(A)
for j=1:n-1
for i=j+1:n
c=A(i,j)/A(j,j)
B(i)=B(i)-B(j)*c
A(i,:)=A(i,:)-A(j,:)*c
end
end
disp('Matriz Triangularizada=')
disp(A)
disp('Vetor b resultante=')
disp(B')
MATRIZ PARA INTERPOLAÇÃO
a = 0; b=0; c=0; d=0; e=0; h=0; m=0;
for i=1:n
a = a + X(i)
b = b + (X(i))^2
c = c + (X(i))^3
d = d + (X(i))^4
m = m + Y(i)
e = e + (Y(i))*(X(i))
h = h + (Y(i))*((X(i))^2)
end