+ }
+}
+
+static void
+group_precalc (struct cmd_t_test *cmd )
+{
+ int i;
+ int j;
+
+ for(i=0; i< cmd->n_variables ; ++i)
+ {
+ struct group_proc *ttpr = group_proc_get (cmd->v_variables[i]);
+
+ /* There's always 2 groups for a T - TEST */
+ ttpr->n_groups = 2;
+
+ gp.indep_width = indep_var->width;
+
+ ttpr->group_hash = hsh_create(2,
+ (hsh_compare_func *) compare_group_binary,
+ (hsh_hash_func *) hash_group_binary,
+ (hsh_free_func *) free_group,
+ (void *) &gp );
+
+ for (j=0 ; j < 2 ; ++j)
+ {
+
+ struct group_statistics *gs = (struct group_statistics *)
+ xmalloc (sizeof(struct group_statistics));
+
+ gs->sum = 0;
+ gs->n = 0;
+ gs->ssq = 0;
+
+ if ( gp.criterion == CMP_EQ )
+ {
+ gs->id = gp.v.g_value[j];
+ }
+ else
+ {
+ if ( j == 0 )
+ gs->id.f = gp.v.critical_value - 1.0 ;
+ else
+ gs->id.f = gp.v.critical_value + 1.0 ;
+ }
+
+ hsh_insert ( ttpr->group_hash, (void *) gs );
+
+ }
+ }
+
+}
+
+static int
+group_calc (const struct ccase *c, struct cmd_t_test *cmd)
+{
+ int i;
+
+ const union value *gv = case_data (c, indep_var->fv);
+
+ const double weight = dict_get_case_weight(default_dict,c,&bad_weight_warn);
+
+ if ( value_is_missing(gv,indep_var) )
+ {
+ return 0;
+ }
+
+ if ( cmd->miss == TTS_LISTWISE )
+ {
+ for(i=0; i< cmd->n_variables ; ++i)
+ {
+ struct variable *v = cmd->v_variables[i];
+ const union value *val = case_data (c, v->fv);
+
+ if (value_is_missing(val,v) )
+ {
+ return 0;
+ }
+ }
+ }
+
+ gv = case_data (c, indep_var->fv);
+
+ for(i=0; i< cmd->n_variables ; ++i)
+ {
+ struct variable *var = cmd->v_variables[i];
+ const union value *val = case_data (c, var->fv);
+ struct hsh_table *grp_hash = group_proc_get (var)->group_hash;
+ struct group_statistics *gs;
+
+ gs = hsh_find(grp_hash, (void *) gv);
+
+ /* If the independent variable doesn't match either of the values
+ for this case then move on to the next case */
+ if ( ! gs )
+ return 0;
+
+ if ( !value_is_missing(val,var) )
+ {
+ gs->n+=weight;
+ gs->sum+=weight * val->f;
+ gs->ssq+=weight * pow2(val->f);
+ }
+ }
+
+ return 0;
+}
+
+
+static void
+group_postcalc ( struct cmd_t_test *cmd )
+{
+ int i;
+
+ for(i=0; i< cmd->n_variables ; ++i)
+ {
+ struct variable *var = cmd->v_variables[i];
+ struct hsh_table *grp_hash = group_proc_get (var)->group_hash;
+ struct hsh_iterator g;
+ struct group_statistics *gs;
+ int count=0;
+
+ for (gs = hsh_first (grp_hash,&g);
+ gs != 0;
+ gs = hsh_next(grp_hash,&g))
+ {
+ gs->mean = gs->sum / gs->n;
+
+ gs->s_std_dev= sqrt(
+ ( (gs->ssq / gs->n ) - gs->mean * gs->mean )
+ ) ;
+
+ gs->std_dev= sqrt(
+ gs->n/(gs->n-1) *
+ ( (gs->ssq / gs->n ) - gs->mean * gs->mean )
+ ) ;
+
+ gs->se_mean = gs->std_dev / sqrt(gs->n);
+ count ++;
+ }
+ assert(count == 2);
+ }
+}
+
+
+
+static void
+calculate(const struct casefile *cf, void *cmd_)
+{
+ struct ssbox stat_summary_box;
+ struct trbox test_results_box;
+
+ struct casereader *r;
+ struct ccase c;
+
+ struct cmd_t_test *cmd = (struct cmd_t_test *) cmd_;