Description
Specify an include file for #calc, expects a single string to follow.
For example if functions from transform.H are used in the #calc expression
\verbatim
angleOfAttack 5; // degs
angle #calc "-degToRad($angleOfAttack)";
#calcInclude "transform.H"
liftDir #calc "transform(Ry($angle), vector(0, 0, 1))";
dragDir #calc "transform(Ry($angle), vector(1, 0, 0))";
\endverbatim
The usual expansion of environment variables and other constructs
(eg, the \c ~OpenFOAM/ expansion) is retained.
See also:
Class
Foam::functionEntries::calcEntry
Description
Uses dynamic compilation to provide calculating functionality
for entering dictionary entries.
E.g.
\verbatim
a 1.0;
b 3;
c #calc "$a*$b";
\endverbatim
Note the explicit trailing 0 ('1.0') to force a to be read (and written)
as a floating point number.
Special care is required for calc entries that include a division since
"/" is also used as the scoping operator to identify keywords in
sub-dictionaries. For example, "$a/b" expects a keyword "b" within a
sub-dictionary named "a". A division can be correctly executed by using a
space between a variables and "/", e.g.
\verbatim
c #calc "$a / $b";
\endverbatim
or "()" scoping around the variable, e.g.
\verbatim
c #calc "($a)/$b";
\endverbatim
Additional include files for the #calc code compilation can be specified
using the #calcInclude entry, e.g. if functions from transform.H are used
\verbatim
angleOfAttack 5; // degs
angle #calc "-degToRad($angleOfAttack)";
#calcInclude "transform.H"
liftDir #calc "transform(Ry($angle), vector(0, 0, 1))";
dragDir #calc "transform(Ry($angle), vector(1, 0, 0))";
\endverbatim
Note:
Internally this is just a wrapper around codeStream functionality - the
#calc string is used to construct a dictionary for codeStream.
The dictionary/table-based expansions provided by stringOps::expand are
now too situation specific for this utility to concisely test with a
single complex string. These expansions are fundamental to the operation
of dictionary and dynamic code and receive good testing coverage in the
tutorial test loop anyway.
Simplifications have been made where possible, as permitted by the new
$<type>var syntax. Duplication has been reduced in similar blockMesh
files (e.g., sloshingTank cases). Settings that cannot practically be
changed have been hard-coded (e.g., angle in the mixerVessel2D
blockMeshDict). The rotor2D blockMeshDict has been centralised and
extended to work with an arbitrary number of rotor blades.
This makes the block/edge/face configuration much more similar between
the four different sections of this mesh. It is also useful as it
permits sections to be decativated by commenting them out without
this affecting all the subsequent numbering.
The purpose of these operations was unclear, and there was no
documentation or examples of their usage. The differences between these
operations behaviours for scalar and vector input seemed arbitrary.
These operations have in some cases become the subject of confusion.
They have therefore been removed.
Equivalent functionality could be easily reinstated as and when a clear
need and application becomes apparent.
Dictionary entries constructed with #calc and #codeStream can now
conveniently access and use typed variables. This means calculations
involving vectors and tensors and list and field types are now possible.
To access a variable and construct it as a given type within a #calc
or #codeStream entry, put the type immediately after the $ symbol inside
angled brackets <>. So, $<vector>var or $<vector>{var} substitutes a
variable named var as a vector.
Examples:
- Reflect a point in a plane defined by a normal
p (1 2 3);
n (1 1 0);
pStar #calc "$<vector>p - (2*sqr($<vector>n)/magSqr($<vector>n)&$<vector>p)";
- Rotate a list of points around an axis by a given angle
points ((3 0 0) (2 1 1) (1 2 2) (0 3 3));
rotation
{
axis (0 1 1);
angle 45;
}
#codeStream
{
codeInclude
#{
#include "pointField.H"
#include "transform.H"
#};
code
#{
const pointField points($<List<point>>points);
const vector axis = $<vector>!rotation/axis;
const scalar angle = degToRad($!rotation/angle);
os << "pointsRotated" << nl << (Ra(axis, angle) & points)() << ";";
#};
};
- Compute the centre and trianglation of a polygon
polygon ((0 0 0) (1 0 0) (2 1 0) (0 2 0) (-1 1 0));
#codeStream
{
codeInclude
#{
#include "polygonTriangulate.H"
#};
code
#{
const List<point> polygon($<List<point>>polygon);
writeEntry(os, "polygonCentre", face::centre(polygon));
polygonTriangulate triEngine;
triEngine.triangulate(polygon);
os << "polygonTris" << ' ' << triEngine.triPoints() << ";";
#};
};
- Generate a single block blockMeshDict for use with snappyHexMesh with no redundant information
min (-2.5 -1.2 -3.0); // Minimum coordinates of the block
max (2.5 1.2 3.0); // Maximum coordinates of the block
nCellsByL 33.3333; // Number of cells per unit length
// Calculate the number of cells in each block direction
nCells #calc "Vector<label>($nCellsByL*($<vector>max - $<vector>min) + vector::one/2)";
// Generate the vertices using a boundBox
vertices #codeStream
{
codeInclude
#{
#include "boundBox.H"
#};
code
#{
os << boundBox($<vector>min, $<vector>max).points();
#};
};
blocks
(
hex (0 1 2 3 4 5 6 7) $nCells simpleGrading (1 1 1)
);
defaultPatch
{
type patch;
}
boundary
();
Specific names have been given for expand functions. Unused functions
have been removed, and functions only used locally have been removed
from the namespace. Documentation has been corrected. Default and
alternative value handling has been removed from code template
expansion.
This allows primitive and other types either directly or indirectly
constructable from Istream to be constructed from a string using pTraits and
IStringStream, e.g.
const vector v(read<vector>("(1 2 3)"));
Variadic constructors have been added to dictionary to facilitate
convenient construction in code, including within a #codeStream entry.
The constructors take an even number of arguments, alternating between
the key and the corresponding value. The values may, themselves, be
dictionaries constructed in the same way. This means that the code
directly maps to the resulting nested dictionary structure.
For example, the following code stream entry:
#codeStream
{
code
#{
writeEntry
(
os,
"dict",
dictionary
(
"s", 1,
"wl", wordList({"apples", "oranges"}),
"subDict", dictionary
(
"v", vector(2, 3, 4),
"t", tensor(5, 6, 7, 8, 9, 10, 11, 12, 13),
"ll", labelList(10, -1)
)
)
);
#};
}
Expands to the following:
dict
{
s 1;
wl 2 ( apples oranges );
subDict
{
v ( 2 3 4 );
t ( 5 6 7 8 9 10 11 12 13 );
ll 10 { -1 };
}
}
setFormat no longer defaults to the value of graphFormat optionally set in
controlDict and must be set in the functionObject dictionary.
boundaryFoam, financialFoam and pdfPlot still require a graphFormat entry in
controlDict but this is now read directly rather than by Time.