0;
v = [5 -1 2 -9 3 4];
function n = vektor1norma(v)
  n = sum(abs(v))
endfunction
function n = vektor1normav2(v)
  n = 0
  h = length(v)
  for i = 1:h
    n = n + abs(v(i))
  endfor
  %% alternativ:
  % for elem = v
  %   n = n + abs(elem)
  % endfor
endfunction
function n = vektor2norma(v)
  n = sqrt(sum(abs(v).^2))
endfunction
function n = vektorInfnorma(v)
  n = max(abs(v))
endfunction
function n = vektor7norma(v)
  n = nthroot(sum(abs(v).^7),7)
endfunction

function n = matrixFrobnorma(A)
  n = sqrt(sum(sum(A.^2)))
endfunction
% 1 norma: oszlop norma
function n = matrix1norma(A)
  n = max(sum(abs(A)))
endfunction
% vegtelen norma: sornorma
% A' : transzponalt, tukrozve foatlora
% avagy: sorok es oszlopok szerepe cserelodik
function n = matrixInfnorma(A)
  n = matrix1norma(A')
  % vagy: n = max(sum(abs(A')))
endfunction
function n = matrix2norma(A)
  n = sqrt(max(abs(eig(A'*A))))
endfunction