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Vectors

Vectors are created "on demand". If a vector, or vector element, appears on the left hand side of an assignment statment then a vector of sufficient size is created to implement the assignment.

For example,

>>V(5) = 3.0;

assigns the value 3.0 to the (5) element of V. If V is not of sufficient size, then V is redimensioned to a vector of length 5 to accomodate the assignment. .

Elements of the vector are accessed using ()'s. A range of indices can be accessed using the : notation, e.g. V(1:3) refers the first three elements of V collectively.

Indexing starts at 1.

The default storage of vectors are as "row" vectors (e.g. 1 x N matrices).

length(V) returns the size of the vector V.

The transpose of a vector can be obtained using the ' operator, or the transpose function.

Element by element operations are implement with the "dot" operators
.+ .- .* ./ .^

If two vectors are not compatable sizes for an algebraic operation, then an error message is generated.

Alternate methods of vector construction can be obtained using []'s. Commas separate vector entries and semi-colons separate rows..

See Also : Operators

Samples

% creating a vector of length 3 initialized to 0.0

 V(3) = 0.0
 V =
     0     0     0

% range access

 V(1:2) = 5.0
 V =
     5     5     0

% create vectors using []'s

 V = [1,2,3,4]  % commas separate row entries
 V =
     1     2     3     4

 W =[1;2;3;4] % semi-colons separate rows
 W =
     1
     2
     3
     4

% create a vector using the range command

 z = 0.0:.2:1.0
 z =
   0    0.2000    0.4000    0.6000    0.8000    1.0000