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.. _field :
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> **_FIELD_**
>
>> The FIELD Command option manipulates one or more specified fields in the
Current Mesh Object
>>
>> *For all points in the specified point set, we compose the field value with
the specified composition function. The composition functions allowed are
currently **asinh** and **log**. So, for example, if 'i' is in the point set
and **asinh** is the composition function, we have the assignment:
>>
>>> field(i) = asinh(field(i)).
>>
>> *The **field**/**mfedraw **command causes a binary dump of the specified
fields to two files in the **mfedraw** input format. **mfedraw** is a graphics
package for visualizing moving piecewise linear functions of two variables,
such as those originally encountered in Moving Finite Elements. The files are
named 'root1.bin' and 'root2.bin', where 'root' is the root file name
argument. Because the graphics data are a function of two variables, you must
supply two orthonormal vectors (x1,y1,z1) and (x2,y2,z2) which specify the
graphics coordinate axes. More precisely, given 3D coordinates (x,y,z), the 2D
graphic coordinates will then be (x*x1+y*y1+z*z1 , x*x2+y*y2+z*z2). So, for
example, the choice:
>>
>>> /x1,y1,z1/x2,y2,z2/ = /1.,0.,0./0.,1.,0./
>>
>> causes the 'z' coordinate to be discarded while the 'x' and 'y' coordinates
are unchanged.
>>
>> *The **field**/**scale** option scales the field values of the specified
points. scale option can take on the values **normalize**, **multiply**, and
**divide**. If **normalize **is specified, we multiply all the field values by
**factor**/(fieldmax-fieldmin), where 'fieldmax' and 'fieldmin' are the
maximum and minimum values taken over the point set. This has the effect of
normalizing the field so that the new difference between the maximum and
minimum values is equal to **factor**. If **multiply** is specified, we
multiply all the field values in the point set by **factor**. If **divide **is
specified, we divide all the field values in the point set by **factor.**
>>
>> *The **field**/**volavg** option, for all the members of the point set and
for all specified fields, replaces the point field values with values that
represent the average of the field(s) over the control volumes associated with
the points. The averaging option specifies what kind of control volume is to
be used; the choices are **voronoi** and** median**. iterations is an integer
that specifies a repeat count for how many times this procedure is to be
performed on the field(s). The affect of this process is to broaden and smooth
the features of the field(s), similar to the effect of a diffusion process.
The **voronoi **choice, unlike the **median**. choice, produces a diffusive
effect independent of mesh connectivity. However, again unlike the **median**.
choice, it _requires_ that the mesh be Delaunay, or incorrect results will
occur.
>
> FORMAT:
>
>> **field**/**compose**/composition function/ifirst,ilast,istride/field list/
**field**/**mfedraw**/root file name/x1,y1,z1/x2,y2,z2/field list/
**field/scale /**scale option/factor/ifirst,ilast,istride/ field list /
**field**/**volavg**/averaging option/iterations/ifirst,ilast,istride/filed list/
>
> EXAMPLES:
>
>> **field**/**compose**/**asinh**/1,0,0/**field**/**scale**/**normalize**/4.*
*field**/**volavg**/**voronoi**/4/1,
>
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