Changes between Version 20 and Version 21 of ModulesOnAstroBear

Timestamp:

07/13/11 15:20:50 (14 years ago)

Author:

ehansen

Comment:

—

ModulesOnAstroBear

@@ -77 +77 @@
 Currently, AstroBEAR can only run 2D and 3D problems, but a 1D hydro or MHD problem can be simulated by defining a very narrow 2D problem domain and then making sure all the activity is defined in the x-direction (i.e., no {{{py}}} or {{{pz}}} components).
 
-The ''core'' region of the {{{Info%q}}} array (which does not include ghost zones) is a {{{1:mx}}} by {{{1:my}}} by {{{1:mz}}} box. Mx, my, and mz denote the number of cells in the x, y, and z directions, respectively.  In two dimensions, {{{mz}}} = 1, reducing the box to a rectangle.  {{{Info%q}}} is cell-centered, so the values are assumed to be taken from the midpoint of the cell.  Thus, the cell-to-space conversion is:
+The ''core'' region of the {{{Info%q}}} array (which does not include ghost zones) is a {{{1:mx}}} by {{{1:my}}} by {{{1:mz}}} box. mx, my, and mz denote the number of cells in the x, y, and z directions, respectively.  In two dimensions, {{{mz}}} = 1, reducing the box to a rectangle.  {{{Info%q}}} is cell-centered, so the values are assumed to be taken from the midpoint of the cell.  Thus, the cell-to-space conversion is:
 
 {{{
 x=(xlower + (REAL(i,xPrec)-half) * dx)
-y=(ylower + (REAL(j,xPrec)-half) * dy)
-z=(zlower + (REAL(k,xPrec)-half) * dz)
+y=(ylower + (REAL(j,xPrec)-half) * dx)
+z=(zlower + (REAL(k,xPrec)-half) * dx)
+}}}
+
+Note that {{{i, j, k, x, y, z, xlower, ylower, zlower, and dx}}} are user defined variables and are explained in further detail below. The variable {{{half}}} is used since the data is in the center of the cell, and {{{xPrec}}} is a type of precision.  {{{half}}} and {{{xPrec}}} are already defined elsewhere and can be used if the following statement is at the beginning of {{{problem.f90}}}:
+{{{
+USE GlobalDeclarations
 }}}
 
@@ -116 +121 @@
 ==== Initializing a Grid ====
 
-Initializing a grid  involves taking a spatially-constructed problem setup and discretizing it so that it fits nicely in an array.  This process is easiest to explain by dissecting an example, such as the one below, where we are trying to initialize the grid with a density distribution given by {{{rho(x,y,z)}}}:
-
-Note that during the !ProblemGridInit routine, ghost zones do not need to be initialized (rmbc = 0) - however - during beforestep calculations they should be
+Initializing a grid  involves taking a spatially-constructed problem setup and discretizing it so that it fits nicely in an array.  This process is easiest to explain by dissecting an example, such as the one below, where we are trying to initialize the grid with a general density distribution given by {{{rho(x,y,z)}}}:
+
+Note that during the !ProblemGridInit routine, ghost zones do not need to be initialized (rmbc = 0) - however - during beforestep calculations they should be.
 
 {{{
@@ -140 +145 @@
             DO i=1-rmbc, mx+rmbc
 
-                x=(xlower + (REAL(i)-half) * dx)
-                y=(ylower + (REAL(j)-half) * dx)
-                z=(zlower + (REAL(k)-half) * dx)
+                x=(xlower + (REAL(i, xPrec)-half) * dx)
+                y=(ylower + (REAL(j, xPrec)-half) * dx)
+                z=(zlower + (REAL(k, xPrec)-half) * dx)
 
                 Info%q(i,j,k,irho) = rho(x,y,z)