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https://github.com/triqs/dft_tools
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49 lines
998 B
ReStructuredText
49 lines
998 B
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.. highlight:: c
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to be removed...
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-------------------------------------------------
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* **Definition** :
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By `expression`, we mean here an object, typically representing a mathematical expression,
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which models the :ref:`HasImmutableArrayInterface` concept.
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* **Use** :
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Expression can be used :
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- as RHS (Right Hand Side) of various operators (=, +=, -=, ...)
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- at any place where an `expression` is expected.
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* **How to make expression ?**
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Expressions can be build easily in various ways :
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- Using :ref:`arith_expression`, e.g. A + 2*B
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- Using predefined expressions, e.g. for Linear Algebra operations.
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For example, in the code::
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matrix<double> M1(2,2), M2(2,2), M3;
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M3 = matmul(M1,M2);
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`matmul` returns an expression, a lazy object modelling the :ref:`Expression` concept.
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REF :
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- Building :ref:`custom_expression`.
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.. toctree::
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:maxdepth: 1
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expr_arith
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expr_predef
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expr_custom
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