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authorThomas White <taw@physics.org>2009-11-16 11:21:52 +0100
committerThomas White <taw@physics.org>2009-11-16 11:21:52 +0100
commit73d3559d7fac9b258ae84954ab08369b9fe10c10 (patch)
tree4d794c64feb577da436c8e998cc0103d7244c4d7 /src/diffraction.c
parent2c3f428648146dc582a46fe74aca9e7474461e3a (diff)
PDB parser
Diffstat (limited to 'src/diffraction.c')
-rw-r--r--src/diffraction.c141
1 files changed, 139 insertions, 2 deletions
diff --git a/src/diffraction.c b/src/diffraction.c
index 902ac008..1a589462 100644
--- a/src/diffraction.c
+++ b/src/diffraction.c
@@ -13,6 +13,8 @@
#include <stdlib.h>
#include <math.h>
#include <stdio.h>
+#include <string.h>
+#include <complex.h>
#include "image.h"
#include "utils.h"
@@ -59,12 +61,144 @@ static double lattice_factor(struct threevec q, double ax, double ay, double az,
}
-static double molecule_factor(struct threevec q)
+static complex get_sfac(const char *n, struct threevec q, double en)
{
+ return 1.0;
+}
+
+
+static double molecule_factor(struct molecule *mol, struct threevec q,
+ double en)
+{
+ int i;
+
+ for ( i=0; i<mol->n_species; i++ ) {
+
+ complex sfac;
+ complex contrib = 0.0;
+ struct mol_species *spec;
+ int j;
+
+ spec = mol->species[i];
+
+ sfac = get_sfac(spec->species, q, en);
+ for ( j=0; j<spec->n_atoms; j++ ) {
+ contrib +=
+ }
+
+ }
+
return 1e5;
}
+static struct molecule *load_molecule()
+{
+ struct molecule *mol;
+ FILE *fh;
+ char line[1024];
+ char *rval;
+ int i;
+
+ mol = malloc(sizeof(struct molecule));
+ if ( mol == NULL ) return NULL;
+ mol->n_species = 0;
+
+ fh = fopen("molecule.pdb", "r");
+ if ( fh == NULL ) {
+ fprintf(stderr, "Couldn't open file\n");
+ return NULL;
+ }
+
+ do {
+
+ char el[4];
+ int i, r;
+ int done = 0;
+ float x, y, z, occ, B;
+ char *coords;
+
+ rval = fgets(line, 1023, fh);
+
+ /* Only interested in atoms */
+ if ( strncmp(line, "HETATM", 6) != 0 ) continue;
+
+ /* The following crimes against programming style
+ * were brought to you by Wizbit Enterprises, Inc. */
+ if ( line[76] == ' ' ) {
+ el[0] = line[77];
+ el[1] = '\0';
+ } else {
+ el[0] = line[76];
+ el[1] = line[77];
+ el[2] = '\0';
+ }
+
+ coords = line + 29;
+ r = sscanf(coords, "%f %f %f %f %f", &x, &y, &z, &occ, &B);
+ if ( r != 5 ) {
+ fprintf(stderr, "WTF?\n");
+ abort();
+ }
+
+ for ( i=0; i<mol->n_species; i++ ) {
+
+ struct mol_species *spec;
+ int n;
+
+ spec = mol->species[i];
+
+ if ( strcmp(spec->species, el) != 0 ) continue;
+
+
+ n = mol->species[i]->n_atoms;
+
+ spec->x[n] = x;
+ spec->y[n] = y;
+ spec->z[n] = z;
+ spec->occ[n] = occ;
+ spec->B[n] = B;
+ mol->species[i]->n_atoms++;
+
+ done = 1;
+
+ }
+
+ if ( !done ) {
+
+ /* Need to create record for this species */
+ struct mol_species *spec;
+
+ spec = malloc(sizeof(struct mol_species));
+
+ memcpy(spec->species, el, 4);
+ spec->x[0] = x;
+ spec->y[0] = y;
+ spec->z[0] = z;
+ spec->occ[0] = occ;
+ spec->B[0] = B;
+ spec->n_atoms = 1;
+
+ mol->species[mol->n_species] = spec;
+ mol->n_species++;
+
+ }
+
+
+ } while ( rval != NULL );
+
+ fclose(fh);
+
+ printf("There are %i species\n", mol->n_species);
+ for ( i=0; i<mol->n_species; i++ ) {
+ printf("'%s': %i\n", mol->species[i]->species,
+ mol->species[i]->n_atoms);
+ }
+
+ return mol;
+}
+
+
void get_diffraction(struct image *image, UnitCell *cell)
{
int x, y;
@@ -74,6 +208,8 @@ void get_diffraction(struct image *image, UnitCell *cell)
/* Generate the array of reciprocal space vectors in image->qvecs */
get_ewald(image);
+ image->molecule = load_molecule();
+ if ( image->molecule == NULL ) return;
cell_get_cartesian(cell, &ax, &ay, &az,
&bx, &by, &bz,
@@ -90,7 +226,8 @@ void get_diffraction(struct image *image, UnitCell *cell)
q = image->qvecs[x + image->width*y];
f_lattice = lattice_factor(q, ax,ay,az,bx,by,bz,cx,cy,cz);
- f_molecule = molecule_factor(q);
+ f_molecule = molecule_factor(image->molecule, q,
+ image->xray_energy);
image->sfacs[x + image->width*y] = f_lattice * f_molecule;