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**
**  MESH CONTROLS
**
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**
**  jx is the number speed mesh points. 
**    Speed also means momentum/rest mass for relativistic calcs.
**    default: jx=300  (in aindflt.f).
**    The basic speed mesh runs from 0. to xmax=1.0.
**
**  iy is the number of theta mesh points. Must be even number.
**    default: iy=200  (in aindflt.f).
**    The y (theta) mesh is symmetric about pi/2.
**    For urfmod.ne."disabled", iy.gt.255 not allowed with 
**      the storage scheme for ilim1,ilim2,....[BH070418: relaxed now?]
**    (Have had difficulty constructing a mesh iy as small as 30, 
**     and meshy.eq."fixed_y".)
**    The positive theta dirn (i.e., v_parallel) has positive component
**       in the positive toroidal direction (counter-clockwise, looking
**       from the top).
**    In some transport settings (transp=.ne."disabled"), the number
**       of theta (y) mesh points may reduce as a function of radius.
**       The y points can also be stacked up around the trapped-passing
**       boundary.   Thus, the y array is two dimensional, y(pitch,rho).
**
**  lz is the number of poloidal (or field line mesh points). Bounce-
**    averages are computed over this mesh. 
**    default: lz=40 (If cqlpmod.eq."enabled", lz is set equal to lsmax)
**
**  vnorm is the velocity normalization constant (cm/sec).
**    For relativistic calculations, vnorm is the maximum momentum/unit
**    rest mass on the mesh.
**    default: vnorm is set through enorm (below).
**    Note that in plots, the variable vnorm is printed as "unorm",
**    to be consistent with meaning of "u" as 
**    the relativ.moment/rest.mass.
**
**  enorm is the energy corresponding to the velocity normalization
**    constant; if kenorm corresponds to a species index, that
**    species determines vnorm through enorm, superseding vnorm. (kev).
**    For relativistic electrons, E=(gamma-1)*m*c**2=(gamma-1)*511. keV.
**                                gamma**2=1+(u/c)**2
**                                u=momentum-per-electron-rest-mass.
**    default: enorm=200., kenorm=1
**
**  tandem="enabled" facilitates the use of both ions and electrons
**    as general species. The mesh extends to a speed (momentum)
**    represented by an electron energy of enorme. However, the
**    majority of the mesh points are dedicated to a region of
**    velocity space which adequately represents ions with a
**    energy less than enormi. The ion species selected for this
**    treatment is the first general ion species listed. Most
**    of the plots are fixed so that the ion contributions are visible
**    and not squeezed into the first 1% of the plot.
**    tandem="disabled" disengages this option.
**    default: tandem="disabled"
**
**  enorme,enormi are analogues to enorm for tandem="enabled"
**    enorme corresponds to the top of the electron mesh,
**    enormi corresponds to the top of the ion mesh.
**    [defaults: enorme=enorm, enormi=enorm]
**
**  relativ="enabled" means the quasi-relativistic calculation and
**    mesh are activated.  Best for fusion plasmas.
**         ="fully" give fully relativistic calc.   Has some limitations
**           in maximum order Legendre polynomial to be used in
**           expansion for FP coefficients (mx, below, .le.3, or so).
**           See CompX report CompX-2009-1_Fully-Rel.pdf.
**    default: relativ="enabled"
**
**  xfac is the velocity mesh spacing parameter.
**    xfac=1. ==> uniform mesh;
**    xfac<1. ==> geometric mesh with greater mesh resolution at x=0;
**    xfac>1. ==> greater resolution at xmax.
**    xfac<0. ==> xpctlwr,xpctmdl,xlwr,xmdl must be input.
**    xfac<0. ==> the momentum (velocity) mesh contains three regions:
**    The region [0,xlwr] will have jx*xpctlwr evenly spaced 
**    mesh points.
**    The region [xlwr,xmdl] will have xpctmdl*jx mesh points.
**    The region [xmdl,xmax] will have the balance of the jx 
**    mesh points.
**    default: xfac=1.
**    (xfac,xpctlwr,xlwr,xpctmdl,xmdl are reset appropriately, if 
**     tandem="enabled").
**
**  tfac is the theta mesh spacing parameter.
**    tfac=1 ==> uniform mesh except in the vicinity of the
**      pass/trapped boundary region. See tbnd below.
**    tfac<1. ==> geometric mesh with points packed closer at p/t bndry.
**    tfac>1. ==> geometric mesh with points packed closer 0., pi, 
**    and pi/2.
**    default: tfac=1.
**  tfac=-1.  ==>Appropriate for radial transport, transp="enabled"
**    calculations.   This will give uniform theta mesh at each 
**    radius.   There will be slight adjustments near t-p bndry
**    at each radius, but no addition of extra points bounding the
**    trapped-passing boundary, as for tfac.gt.0. case.
**    If tfac.gt.0. and transp="enabled" and soln_method.ne."direct"
**    then tfac is reset to -1. at beginning of run.
**    
**    If tfac negative and .ne.-1, then mesh adjusted according to 
**    positive tfac above, with abs(tfac) values.  No added pts near t-p.
**  There is also a tfac.lt.0./cqlpmod="enabled" option (see below).
**
**  yreset="enabled" means pack extra theta mesh points in some
**    specified (below) region.
**    default:yreset="disabled"
**    [Not working at present, and if "enabled" will be reset to
**     "disabled" in ainsetva.f, for lrz>1.] 
**
**  numby is the number of packed theta mesh points
**    numby should be significantly less than iy/2 (or resolution
**    will be to coarse in the rest of pitch angle space).
**    Recall that the y (theta) mesh is symmetric about pi/2.
**    Only used if yreset="enabled".
**    default: numby=20
**
**  ylower and yupper specify the radian spread of the packed region
**    below pi/2. Avoid allowing [ylower,yupper] to include the p/t
**    boundary region [y(itl-1),y(itl+1)].
**    This option is automatically disabled if lrz > 1.
**    Only used if yreset="enabled".
**
**  tfacz is the field line coordinate (z) mesh spacing parameter.
**    default: tfacz=1.
**    tfacz is not operational for eqsym="none", in which case the z-mesh
**    is uniform on either side of the max-|B| point on the flux surface.
**
**  tbnd(1:lrorsa) is the width (in radians) of the passing/trapped boundary 
**    layer. There is usually no reason to change the default value.
**    If necessary the program may reset this value at some
**    flux surfaces.
**    default: tbnd(1)=.002, tbnd(2:lrorsa)=0.
**
**  rfacz is the radial mesh spacing parameter. The minimum value of
**    the mesh can be pre-specified (see roveram below). Otherwise
**    rfacz works like xfac for xfac > 0.
**    default:rfacz=.7
**
**  roveram determines the value of r/radmin = rya(1) by setting
**    rya(1)=roveram.   It works in conjunction with
**    rfacz above. If roveram < 1.e-8, the minimum flux surface is
**    determined internally with no user control. This option is
**    useful for keeping the innermost flux surface away from the
**    magnetic axis.
**    default: roveram=1.e-8
**
**  rzset="enabled" allows the user to specify the entire radial
**    rya mesh as an array of values r(l)/radmin where r(l) is the
**    radial coordinate and radmin in this case takes on
**    the meaning of the radial coodinate at the LCFS.
**    ="disabled", mesh follows rfacz directive, above.
**    default: rzset="disabled"
**
**  rya(l),l=1,lrzmax is the normalized radial mesh referred to above in
**    the rzset description. The user specifies rya(1)=.02, rya(2)=.05,...
**    rya(23)=.95, for instance, if lrzmax=23
**    Thus rya(l)=r(l)/radmin, and rya is a code array.
**    (Note: rya is dimensioned rya(0:lrza+1), so need to specify
**    first namelist input value explicitly as rya(1)=....).
**
**  radcoord="sqtorflx" (default) use normalized radial coordinate (that is,
**           flux surface label) proportional to sqrt of toroidal flux.
**           [Presently, radial diffusion eqn is only set up for this value
**            of radcoord.  Additional choices below are for no radial 
**            transport.]
**          ="sqarea" square root of flux surface area,
**          ="sqvol" square root of flux surface volume,
**          ="rminmax" 0.5*(max. major radius - 
**                          min. major radius) of flux surface
**          "polflx"  normalized poloidal flux from magnetic
**                    axis to last closed flux surface (LCFS).
**          "sqpolflx"  normalized square root of poloidal flux function.
**
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