h=[0.01,0.02,0.03]

h =

    0.0100    0.0200    0.0300

x=[0,0.01,0.02,0.035,0.04,0.06]

x =

  Columns 1 through 4

         0    0.0100    0.0200    0.0350

  Columns 5 through 6

    0.0400    0.0600

h=x(2:6)-x(1:5)

h =

  Columns 1 through 4

    0.0100    0.0100    0.0150    0.0050

  Column 5

    0.0200

h=diff(x)

h =

  Columns 1 through 4

    0.0100    0.0100    0.0150    0.0050

  Column 5

    0.0200

1./h

ans =

  Columns 1 through 4

  100.0000  100.0000   66.6667  200.0000

  Column 5

   50.0000

1./(h(1:4)+1./h(2:5)
??? 1./(h(1:4)+1./h(2:5)
                        |
Error: Expression or statement is
incorrect--possibly unbalanced (, {, or [.

1./h(1:4)+1./h(2:5)

ans =

  200.0000  166.6667  266.6667  250.0000

d=1./h(1:4)+1./h(2:5)

d =

  200.0000  166.6667  266.6667  250.0000

d=[1/h(1),1./h(1:4)+1./h(2:5),1/h(5)]

d =

  Columns 1 through 4

  100.0000  200.0000  166.6667  266.6667

  Columns 5 through 6

  250.0000   50.0000

diag(d)

ans =

  Columns 1 through 4

  100.0000         0         0         0
         0  200.0000         0         0
         0         0  166.6667         0
         0         0         0  266.6667
         0         0         0         0
         0         0         0         0

  Columns 5 through 6

         0         0
         0         0
         0         0
         0         0
  250.0000         0
         0   50.0000

spdiags(d,0,6,6)
??? Index exceeds matrix dimensions.

Error in ==> <a href="matlab: opentoline('/usr/local/matlab_R2008A/toolbox/matlab/sparfun/spdiags.m',114,0)">spdiags at 114</a>
         a((len(k)+1):len(k+1),:) = [i i+d(k)
         B(i+(m>=n)*d(k),k)];

d=[1/h(1),1./h(1:4)+1./h(2:5),1/h(5)]';
spdiags(d,0,6,6)

ans =

   (1,1)     100.0000
   (2,2)     200.0000
   (3,3)     166.6667
   (4,4)     266.6667
   (5,5)     250.0000
   (6,6)      50.0000

a=[1;2;3;4]

a =

     1
     2
     3
     4

b=[5,6,7,8];
c=[9;10;11;12];
b=b';
spdiags([a,b,c],[-1,0,1],4,4)

ans =

   (1,1)        5
   (2,1)        1
   (1,2)       10
   (2,2)        6
   (3,2)        2
   (2,3)       11
   (3,3)        7
   (4,3)        3
   (3,4)       12
   (4,4)        8

A=spdiags([a,b,c],[-1,0,1],4,4);
full(A)

ans =

     5    10     0     0
     1     6    11     0
     0     2     7    12
     0     0     3     8

uiopen('/home/accounts/personale/clrmrc90/aa1112/equazioni_differenziali/fourier.m', true);
i

ans =

        0 + 1.0000i

for i=1:10
disp('ciao')
end
ciao
ciao
ciao
ciao
ciao
ciao
ciao
ciao
ciao
ciao
i

i =

    10

1i

ans =

        0 + 1.0000i

2i

ans =

        0 + 2.0000i

% Modify expression to add input arguments.
% Example:
%   a = [1 2 3; 4 5 6]; 
%   foo(a);

fourier
x

x =

   -3.1416
   -3.0925
   -3.0434
   -2.9943
   -2.9452
   -2.8962
   -2.8471
   -2.7980
   -2.7489
   -2.6998
   -2.6507
   -2.6016
   -2.5525
   -2.5035
   -2.4544
   -2.4053
   -2.3562
   -2.3071
   -2.2580
   -2.2089
   -2.1598
   -2.1108
   -2.0617
   -2.0126
   -1.9635
   -1.9144
   -1.8653
   -1.8162
   -1.7671
   -1.7181
   -1.6690
   -1.6199
   -1.5708
   -1.5217
   -1.4726
   -1.4235
   -1.3744
   -1.3254
   -1.2763
   -1.2272
   -1.1781
   -1.1290
   -1.0799
   -1.0308
   -0.9817
   -0.9327
   -0.8836
   -0.8345
   -0.7854
   -0.7363
   -0.6872
   -0.6381
   -0.5890
   -0.5400
   -0.4909
   -0.4418
   -0.3927
   -0.3436
   -0.2945
   -0.2454
   -0.1963
   -0.1473
   -0.0982
   -0.0491
         0
    0.0491
    0.0982
    0.1473
    0.1963
    0.2454
    0.2945
    0.3436
    0.3927
    0.4418
    0.4909
    0.5400
    0.5890
    0.6381
    0.6872
    0.7363
    0.7854
    0.8345
    0.8836
    0.9327
    0.9817
    1.0308
    1.0799
    1.1290
    1.1781
    1.2272
    1.2763
    1.3254
    1.3744
    1.4235
    1.4726
    1.5217
    1.5708
    1.6199
    1.6690
    1.7181
    1.7671
    1.8162
    1.8653
    1.9144
    1.9635
    2.0126
    2.0617
    2.1108
    2.1598
    2.2089
    2.2580
    2.3071
    2.3562
    2.4053
    2.4544
    2.5035
    2.5525
    2.6016
    2.6507
    2.6998
    2.7489
    2.7980
    2.8471
    2.8962
    2.9452
    2.9943
    3.0434
    3.0925

plot(x,1./(sin(x)+2))
plot(x,1./(sin(x)+2))
fourier
% Modify expression to add input arguments.
% Example:
%   a = [1 2 3; 4 5 6]; 
%   foo(a);

fourier
diary off