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Container Concepts

Vector

Description

A Vector describes common aspects of dense, packed and sparse vectors.

Refinement of

DefaultConstructible, RandomAccessContainer and Vector Expression [1].

Associated types

In addition to the types defined by RandomAccessContainer and Vector Expression

Public base vector_container<V> V must be derived from this public base type.
Storage array V::array_type Dense Vector ONLY. The type of underlying storage array used to store the elements. The array_type must model the Storage concept.

Notation

V A type that is a model of Vector
v Objects of type V
n, i Objects of a type convertible to size_type
t Object of a type convertible to value_type
p Object of a type convertible to bool

Definitions

Valid expressions

In addition to the expressions defined in DefaultConstructible, RandomAccessContainer and Vector Expression the following expressions must be valid.

Name Expression Type requirements Return type
Sizing constructor V v (n)   V
Insert v.insert_element (i, t) v is mutable. void
Erase v.erase_element (i) v is mutable. void
Clear v.clear () v is mutable. void
Resize v.resize (n)
v.resize (n, p)
v is mutable. void
Storage v.data() v is mutable and Dense. array_type& if a is mutable, const array_type& otherwise

Expression semantics

Semantics of an expression is defined only where it differs from, or is not defined in Vector Expression .

Name Expression Precondition Semantics Postcondition
Sizing constructor V v (n) n >= 0 Allocates a vector ofn elements. v.size () == n.
Element access [2] v[n] 0<n>v.size() returns the n-th element in v  
Insert v.insert_element (i, t) 0 <= i < v.size (). Inserts an element at v (i) with value t. The storage requirement of the Vector may be increased. v (i) is equal to t.
Erase v.erase_element (i) 0 <= i < v.size () Destroys the element as v (i) and replaces it with the default value_type (). The storage requirement of the Vector may be decreased. v (i) is equal to value_type ().
Clear v.clear ()   Equivalent to
for (i = 0; i < v.size (); ++ i)
  v.erase_element (i);
 
Resize v.resize (n)
v.resize (n, p)
  Reallocates the vector so that it can hold n elements.
Erases or appends elements in order to bring the vector to the prescribed size. Appended elements copies of value_type().
When p == false then existing elements are not preserved and elements will not appended as normal. Instead the vector is in the same state as that after an equivalent sizing constructor.
v.size () == n.
Storage v.data() Returns a reference to the underlying dense storage.  

Complexity guarantees

The run-time complexity of the sizing constructor is linear in the vector's size.

The run-time complexity of insert_element and erase_element is specific for the Vector model and it depends on increases/decreases in storage requirements.

The run-time complexity of resize is linear in the vector's size.

Invariants

Models

Notes

[1] As a user you need not care about Vector being a refinement of the VectorExpression. Being a refinement of the VectorExpression is only important for the template-expression engine but not the user.

[2] The operator[] is added purely for convenience and compatibility with the std::vector. In uBLAS however, generally operator() is used for indexing because this can be used for both vectors and matrices.

Matrix

Description

A Matrix describes common aspects of dense, packed and sparse matrices.

Refinement of

DefaultConstructible, Matrix Expression [1] .

Associated types

In addition to the types defined by RandomAccessContainer and Matrix Expression

Public base matrix_container<M> M must be derived from this public base type.
Storage array M::array_type Dense Matrix ONLY. The type of underlying storage array used to store the elements. The array_type must model the Storage concept.

Notation

M A type that is a model of Matrix
m Objects of type M
n1, n2, i, j Objects of a type convertible to size_type
t Object of a type convertible to value_type
p Object of a type convertible to bool

Definitions

Valid expressions

In addition to the expressions defined in Matrix Expression the following expressions must be valid.

Name Expression Type requirements Return type
Sizing constructor M m (n1, n2)   M
Insert m.insert_element (i, j, t) m is mutable. void
Erase m.erase_element (i, j) m is mutable. void
Clear m.clear () m is mutable. void
Resize m.resize (n1, n2)
m.resize (n1, n2, p)
m is mutable. void
Storage m.data() m is mutable and Dense. array_type& if a is mutable, const array_type& otherwise

Expression semantics

Semantics of an expression is defined only where it differs from, or is not defined in Matrix Expression .

Name Expression Precondition Semantics Postcondition
Sizing constructor M m (n1, n2) n1 >= 0 and n2 >= 0 Allocates a matrix of n1 rows and n2 columns. m.size1 () == n1 and m.size2 () == n2.
Insert m.insert_element (i, j, t) 0 <= i < m.size1 (),
0 <= j < m.size2 ().
Inserts an element at m (i, j) with value t. The storage requirement of the Matrix may be increased. m (i, j) is equal to t.
Erase m.erase_element (i, j) 0 <= i < m.size1 ()and
0 <= j < m.size2
Destroys the element as m (i, j) and replaces it with the default value_type (). The storage requirement of the Matrix may be decreased. m (i, j) is equal to value_type ().
Clear m.clear ()   Equivalent to
for (i = 0; i < m.size1 (); ++ i)
  for (j = 0; j < m.size2 (); ++ j)
    m.erase_element (i, j);
 
Resize m.resize (n1, n2)
m.resize (n1, n2, p)
  Reallocate the matrix so that it can hold n1 rows and n2 columns.
Erases or appends elements in order to bring the matrix to the prescribed size. Appended elements are value_type() copies.
When p == false then existing elements are not preserved and elements will not appended as normal. Instead the matrix is in the same state as that after an equivalent sizing constructor.
m.size1 () == n1 and m.size2 () == n2.
Storage m.data() Returns a reference to the underlying dense storage.  

Complexity guarantees

The run-time complexity of the sizing constructor is quadratic in the matrix's size.

The run-time complexity of insert_element and erase_element is specific for the Matrix model and it depends on increases/decreases in storage requirements.

The run-time complexity of resize is quadratic in the matrix's size.

Invariants

Models

Notes

[1] As a user you need not care about Matrix being a refinement of the MatrixExpression. Being a refinement of the MatrixExpression is only important for the template-expression engine but not the user.


Copyright (©) 2000-2002 Joerg Walter, Mathias Koch
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