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Diffstat (limited to 'src/GeneralizedPolynomial-Uniform/molecule_posn.c')
| -rw-r--r-- | src/GeneralizedPolynomial-Uniform/molecule_posn.c | 238 |
1 files changed, 0 insertions, 238 deletions
diff --git a/src/GeneralizedPolynomial-Uniform/molecule_posn.c b/src/GeneralizedPolynomial-Uniform/molecule_posn.c deleted file mode 100644 index 6d42ef3..0000000 --- a/src/GeneralizedPolynomial-Uniform/molecule_posn.c +++ /dev/null @@ -1,238 +0,0 @@ - /*@@ - @file molecule_posn.c - @date 23 Oct 2001 - @author Jonathan Thornburg <jthorn@aei.mpg.de> - @desc Worker function to compute molecule positions for interpolator. - @enddesc - @version $Id$ - @@*/ - -#include <math.h> -#include <stdlib.h> -#include <stdio.h> - -#ifndef LOCALINTERP_STANDALONE_BUILD - #include "cctk.h" -#endif - -#include "InterpLocalUniform.h" - -/* the rcs ID and its dummy function to use it */ -static const char *rcsid = "$Header$"; -#ifndef LOCALINTERP_STANDALONE_BUILD - CCTK_FILEVERSION(CactusBase_LocalInterp_src_GeneralizedPolynomialUniform_molecule_posn_c) -#endif - -/******************************************************************************/ -/******************************************************************************/ -/******************************************************************************/ - -/*@@ - @routine LocalInterp_molecule_posn - @date 23 Oct 2001 - @author Jonathan Thornburg <jthorn@aei.mpg.de> - @desc - Given a uniformly-spaced grid, this function computes molecule - positions for an interpolation or similar operation: - (1) It computes the closest grid point to the input coordinate - (2) It does the slightly tricky odd/even computation to decide where - to center the molecule - (3) It checks for the molecule falling off the edge of the grid, - and off-centers it as appropriate. - - For (1), we assume that grid points have floating-point - coordinates (we refer to these as "x") which are an arbitrary - linear function of the integer grid coordinates (we refer to - these as "i"), x = grid_origin + i*grid_delta. - - For (2), suppose we have a data array indexed by [i], from which we - wish to select an N-point molecule [i_lo, i_hi] centered as close as - possible to the point x . The problem is just how to choose the - centering. The following diagram illustrates the issues: - - N i_lo i_hi [i-3] [i-2] [i-1] [i] [i+1] [i+2] [i+3] [i+4] - - ---- ---- ----- ----- ----- ----- ----- ----- ----- ----- - 2 i i+1 *xxxxxx* - 3 i-1 i+1 * xxx*xxx * - 4 i-1 i+2 * *xxxxxx* * - 5 i-2 i+2 * * xxx*xxx * * - 6 i-2 i+3 * * *xxxxxx* * * - 7 i-3 i+3 * * * xxx*xxx * * * - 8 i-3 i+4 * * * *xxxxxx* * * * - - The diagram shows the range of x values relative to the grid, - for which we'll choose each centering. Thus if N is even, the - centering is based on which grid zone contains x (take the floor - of the floating-point i coordinate), while if N is odd, the centering - is based on which grid point is closest to x (round the floating- - -point i coordinate to the nearest integer). - - It's also convenient to introduce the integer molecule coordinate m; - this is the integer grid coordinate i relative to that of the molecule - center, i.e. the above diagram has columns labelled with [i+m]. - @enddesc - - @hdate 27.Jan.2003 - @hauthor Jonathan Thornburg <jthorn@aei.mpg.de> - @hdesc Complete rewrite: now supports - @var boundary_off_centering_tolerance_min, - @var boundary_off_centering_tolerance_max, - @var boundary_extrapolation_tolerance_min, - @var boundary_extrapolation_tolerance_max, - also change to returning status code, - also drop returning @var min_m and @var max_m - since they were never used. - @endhdesc - - @var grid_origin - @vdesc The floating-point coordinate x of the grid point i=0. - @vtype fp grid_origin - @endvar - - @var grid_delta - @vdesc The grid spacing (in the floating-point coordinate x). - @vtype fp grid_delta - @endvar - - @var grid_i_min - @vdesc The minimum integer coordinate i of the grid. - @vtype int grid_i_min - @endvar - - @var grid_i_max - @vdesc The maximum integer coordinate i of the grid. - @vtype int grid_i_max - @endvar - - @var molecule_size - @vdesc The size (number of points) of the molecule. - @vtype int molecule_size - @endvar - - @var boundary_off_centering_tolerance_min, - boundary_off_centering_tolerance_max - @vdesc Specifies how many grid spacings the interpolation point - may be beyond the default-centering region before being - declared "out of range" on the {minimum,maximum} boundaries - of the grid respectively. - @vtype fp boundary_off_centering_tolerance_min, - boundary_off_centering_tolerance_max - @endvar - - @var boundary_extrapolation_tolerance_min, - boundary_extrapolation_tolerance_max - @vdesc Specifies how many grid spacings the interpolation point - may be beyond the grid boundary before being declared - "out of range" on the {minimum,maximum} boundaries - of the grid respectively. - @vtype fp boundary_extrapolation_tolerance_min, - boundary_extrapolation_tolerance_max - @endvar - - @var x - @vdesc The floating-point coordinate of the interpolation point. - @vtype fp x - @endvar - - @var i_center - @vdesc A pointer to an value where this function should - store the integer coordinate of the molecule center, - or NULL to skip storing this - @vtype int *i_center - @vio pointer to out - @endvar - - @var x_rel - @vdesc A pointer to where this function should store the - interpolation point's x coordinate relative to the - molecule center, measured in units of the grid spacing; - or NULL to skip storing this. - @vtype fp *x_rel - @vio pointer to out - @endvar - - @returntype int - @returndesc - This function returns 0 if the interpolation point is "in range", - or one of the (negative) error codes defined in "InterpLocalUniform.h" - if the interpolation point is "out of range": - MOLECULE_POSN_ERROR_X_LT_MIN - if x is out-of-range on the min end of the grid - (i.e. x < the minimum allowable x) - MOLECULE_POSN_ERROR_X_GT_MAX - if x is out-of-range on the max end of the grid - (i.e. x > the maximum allowable x) - MOLECULE_POSN_ERROR_GRID_TINY - if the grid is smaller than the molecule - @endreturndesc - @@*/ -int LocalInterp_molecule_posn(fp grid_origin, fp grid_delta, - int grid_i_min, int grid_i_max, - int molecule_size, - fp boundary_off_centering_tolerance_min, - fp boundary_off_centering_tolerance_max, - fp boundary_extrapolation_tolerance_min, - fp boundary_extrapolation_tolerance_max, - fp x, - int* i_center, fp* x_rel) -{ -/* molecule radia (inherently positive) in +/- directions */ -const int mr_plus = (molecule_size >> 1); -const int mr_minus = molecule_size - mr_plus - 1; - -/* range of x_rel for which this molecule is centered, cf. diagram in header comment */ -const fp centered_min_x_rel = IS_EVEN(molecule_size) ? 0.0 : -0.5; -const fp centered_max_x_rel = IS_EVEN(molecule_size) ? 1.0 : +0.5; - -/* range of i where we *could* center the molecule, as floating-point numbers */ -const fp fp_centered_min_possible_i = grid_i_min + mr_minus + centered_min_x_rel; -const fp fp_centered_max_possible_i = grid_i_max - mr_plus + centered_max_x_rel; - -/* integer coordinate i of interpolation point, as a floating-point number */ -const fp fp_i = (x - grid_origin) / grid_delta; - -/* is the molecule larger than the grid? */ -if (molecule_size > HOW_MANY_IN_RANGE(grid_i_min,grid_i_max)) - then return MOLECULE_POSN_ERROR_GRID_TINY; /*** ERROR RETURN ***/ - -/* is interpolation point x beyond the extrapolation tolerance? */ -if (fp_i < (fp)grid_i_min - boundary_extrapolation_tolerance_min) - then return MOLECULE_POSN_ERROR_X_LT_MIN; /*** ERROR RETURN ***/ -if (fp_i > (fp)grid_i_max + boundary_extrapolation_tolerance_max) - then return MOLECULE_POSN_ERROR_X_GT_MAX; /*** ERROR RETURN ***/ - -/* is interpolation point x beyond the off-centering tolerance? */ -if (fp_i < fp_centered_min_possible_i - boundary_off_centering_tolerance_min) - then return MOLECULE_POSN_ERROR_X_LT_MIN; /*** ERROR RETURN ***/ -if (fp_i > fp_centered_max_possible_i + boundary_off_centering_tolerance_max) - then return MOLECULE_POSN_ERROR_X_GT_MAX; /*** ERROR RETURN ***/ - -/* now choose the actual molecule position/centering: */ -/* first set up a centered molecule */ - { -fp fp_i_center = IS_EVEN(molecule_size) /* ... as a floating-point number */ - ? floor(fp_i) - : JT_ROUND(fp_i); -int int_i_center = (int) fp_i_center; /* ... as an integer */ - -/* then clamp the molecule at the grid boundaries */ -if (int_i_center - mr_minus < grid_i_min) - then { - int_i_center = grid_i_min + mr_minus; - fp_i_center = (fp) int_i_center; - } -if (int_i_center + mr_plus > grid_i_max) - then { - int_i_center = grid_i_max - mr_plus; - fp_i_center = (fp) int_i_center; - } - -/* store the results */ -if (i_center != NULL) - then *i_center = int_i_center; -if (x_rel != NULL) - then *x_rel = fp_i - fp_i_center; - -return 0; /*** NORMAL RETURN ***/ - } -} |