src/rt/data.c

#ifndef lint
static const char       RCSid[] = "$Id: data.c,v 2.26 2004/01/02 11:43:42 schorsch Exp $";
#endif
/*
 *  data.c - routines dealing with interpolated data.
 */

#include "copyright.h"

#include  <time.h>

#include  "platform.h"
#include  "standard.h"
#include  "color.h"
#include  "resolu.h"
#include  "view.h"
#include  "data.h"

                                /* picture memory usage before warning */
#ifndef PSIZWARN
#ifdef SMLMEM
#define PSIZWARN        1500000
#else
#define PSIZWARN        5000000
#endif
#endif

#ifndef TABSIZ
#define TABSIZ          97              /* table size (prime) */
#endif

#define hash(s)         (shash(s)%TABSIZ)


static DATARRAY  *dtab[TABSIZ];         /* data array list */

static gethfunc headaspect;


extern DATARRAY *
getdata(                                /* get data array dname */
        char  *dname
)
{
        char  *dfname;
        FILE  *fp;
        int  asize;
        register int  i, j;
        register DATARRAY  *dp;
                                                /* look for array in list */
        for (dp = dtab[hash(dname)]; dp != NULL; dp = dp->next)
                if (!strcmp(dname, dp->name))
                        return(dp);             /* found! */
        /*
         *      If we haven't loaded the data already, we will look
         *  for it in the directories specified by the library path.
         *
         *      The file has the following format:
         *
         *              N
         *              beg0    end0    n0
         *              beg1    end1    n1
         *              . . .
         *              begN    endN    nN
         *              data, later dimensions changing faster
         *              . . .
         *
         *      For irregularly spaced points, the following can be
         *  substituted for begi endi ni:
         *
         *              0 0 ni p0i p1i .. pni
         */

        if ((dfname = getpath(dname, getrlibpath(), R_OK)) == NULL) {
                sprintf(errmsg, "cannot find data file \"%s\"", dname);
                error(USER, errmsg);
        }
        if ((fp = fopen(dfname, "r")) == NULL) {
                sprintf(errmsg, "cannot open data file \"%s\"", dfname);
                error(SYSTEM, errmsg);
        }
                                                        /* get dimensions */
        if (fgetval(fp, 'i', (char *)&asize) <= 0)
                goto scanerr;
        if ((asize <= 0) | (asize > MAXDDIM)) {
                sprintf(errmsg, "bad number of dimensions for \"%s\"", dname);
                error(USER, errmsg);
        }
        if ((dp = (DATARRAY *)malloc(sizeof(DATARRAY))) == NULL)
                goto memerr;
        dp->name = savestr(dname);
        dp->type = DATATY;
        dp->nd = asize;
        asize = 1;
        for (i = 0; i < dp->nd; i++) {
                if (fgetval(fp, DATATY, (char *)&dp->dim[i].org) <= 0)
                        goto scanerr;
                if (fgetval(fp, DATATY, (char *)&dp->dim[i].siz) <= 0)
                        goto scanerr;
                if (fgetval(fp, 'i', (char *)&dp->dim[i].ne) <= 0)
                        goto scanerr;
                if (dp->dim[i].ne < 2)
                        goto scanerr;
                asize *= dp->dim[i].ne;
                if ((dp->dim[i].siz -= dp->dim[i].org) == 0) {
                        dp->dim[i].p = (DATATYPE *)
                                        malloc(dp->dim[i].ne*sizeof(DATATYPE));
                        if (dp->dim[i].p == NULL)
                                goto memerr;
                        for (j = 0; j < dp->dim[i].ne; j++)
                                if (fgetval(fp, DATATY,
                                                (char *)&dp->dim[i].p[j]) <= 0)
                                        goto scanerr;
                        for (j = 1; j < dp->dim[i].ne-1; j++)
                                if ((dp->dim[i].p[j-1] < dp->dim[i].p[j]) !=
                                        (dp->dim[i].p[j] < dp->dim[i].p[j+1]))
                                        goto scanerr;
                        dp->dim[i].org = dp->dim[i].p[0];
                        dp->dim[i].siz = dp->dim[i].p[dp->dim[i].ne-1]
                                                - dp->dim[i].p[0];
                } else
                        dp->dim[i].p = NULL;
        }
        if ((dp->arr.d = (DATATYPE *)malloc(asize*sizeof(DATATYPE))) == NULL)
                goto memerr;
        
        for (i = 0; i < asize; i++)
                if (fgetval(fp, DATATY, (char *)&dp->arr.d[i]) <= 0)
                        goto scanerr;
        fclose(fp);
        i = hash(dname);
        dp->next = dtab[i];
        return(dtab[i] = dp);

memerr:
        error(SYSTEM, "out of memory in getdata");
scanerr:
        sprintf(errmsg, "%s in data file \"%s\"",
                        feof(fp) ? "unexpected EOF" : "bad format", dfname);
        error(USER, errmsg);
        return NULL; /* pro forma return */
}


static int
headaspect(                     /* check string for aspect ratio */
        char  *s,
        void  *iap
)
{
        char    fmt[32];

        if (isaspect(s))
                *(double*)iap *= aspectval(s);
        else if (formatval(fmt, s) && !globmatch(PICFMT, fmt))
                *(double*)iap = 0.0;
        return(0);
}


extern DATARRAY *
getpict(                                /* get picture pname */
        char  *pname
)
{
        double  inpaspect;
        char  *pfname;
        FILE  *fp;
        COLR  *scanin;
        int  sl, ns;
        RESOLU  inpres;
        RREAL  loc[2];
        int  y;
        register int  x, i;
        register DATARRAY  *pp;
                                                /* look for array in list */
        for (pp = dtab[hash(pname)]; pp != NULL; pp = pp->next)
                if (!strcmp(pname, pp->name))
                        return(pp);             /* found! */

        if ((pfname = getpath(pname, getrlibpath(), R_OK)) == NULL) {
                sprintf(errmsg, "cannot find picture file \"%s\"", pname);
                error(USER, errmsg);
        }
        if ((pp = (DATARRAY *)malloc(3*sizeof(DATARRAY))) == NULL)
                goto memerr;

        pp[0].name = savestr(pname);

        if ((fp = fopen(pfname, "r")) == NULL) {
                sprintf(errmsg, "cannot open picture file \"%s\"", pfname);
                error(SYSTEM, errmsg);
        }
        SET_FILE_BINARY(fp);
                                                /* get dimensions */
        inpaspect = 1.0;
        getheader(fp, headaspect, &inpaspect);
        if (inpaspect <= FTINY || !fgetsresolu(&inpres, fp))
                goto readerr;
        pp[0].nd = 2;
        pp[0].dim[0].ne = inpres.yr;
        pp[0].dim[1].ne = inpres.xr;
        pp[0].dim[0].org =
        pp[0].dim[1].org = 0.0;
        if (inpres.xr <= inpres.yr*inpaspect) {
                pp[0].dim[0].siz = inpaspect *
                                        (double)inpres.yr/inpres.xr;
                pp[0].dim[1].siz = 1.0;
        } else {
                pp[0].dim[0].siz = 1.0;
                pp[0].dim[1].siz = (double)inpres.xr/inpres.yr /
                                        inpaspect;
        }
        pp[0].dim[0].p = pp[0].dim[1].p = NULL;
        sl = scanlen(&inpres);                          /* allocate array */
        ns = numscans(&inpres);
        i = ns*sl*sizeof(COLR);
#if PSIZWARN
        if (i > PSIZWARN) {                             /* memory warning */
                sprintf(errmsg, "picture file \"%s\" using %d bytes of memory",
                                pname, i);
                error(WARNING, errmsg);
        }
#endif
        if ((pp[0].arr.c = (COLR *)malloc(i)) == NULL)
                goto memerr;
                                                        /* load picture */
        if ((scanin = (COLR *)malloc(sl*sizeof(COLR))) == NULL)
                goto memerr;
        for (y = 0; y < ns; y++) {
                if (freadcolrs(scanin, sl, fp) < 0)
                        goto readerr;
                for (x = 0; x < sl; x++) {
                        pix2loc(loc, &inpres, x, y);
                        i = (int)(loc[1]*inpres.yr)*inpres.xr +
                                        (int)(loc[0]*inpres.xr);
                        copycolr(pp[0].arr.c[i], scanin[x]);
                }
        }
        free((void *)scanin);
        fclose(fp);
        i = hash(pname);
        pp[0].next = dtab[i];           /* link into picture list */
        pp[1] = pp[0];
        pp[2] = pp[0];
        pp[0].type = RED;               /* differentiate RGB records */
        pp[1].type = GRN;
        pp[2].type = BLU;
        return(dtab[i] = pp);

memerr:
        error(SYSTEM, "out of memory in getpict");
readerr:
        sprintf(errmsg, "bad picture file \"%s\"", pfname);
        error(USER, errmsg);
        return NULL; /* pro forma return */
}


extern void
freedata(                       /* release data array reference */
        DATARRAY  *dta
)
{
        DATARRAY  head;
        int  hval, nents;
        register DATARRAY  *dpl, *dp;
        register int  i;

        if (dta == NULL) {                      /* free all if NULL */
                hval = 0; nents = TABSIZ;
        } else {
                hval = hash(dta->name); nents = 1;
        }
        while (nents--) {
                head.next = dtab[hval];
                dpl = &head;
                while ((dp = dpl->next) != NULL)
                        if ((dta == NULL) | (dta == dp)) {
                                dpl->next = dp->next;
                                if (dp->type == DATATY)
                                        free((void *)dp->arr.d);
                                else
                                        free((void *)dp->arr.c);
                                for (i = 0; i < dp->nd; i++)
                                        if (dp->dim[i].p != NULL)
                                                free((void *)dp->dim[i].p);
                                freestr(dp->name);
                                free((void *)dp);
                        } else
                                dpl = dp;
                dtab[hval++] = head.next;
        }
}


extern double
datavalue(              /* interpolate data value at a point */
        register DATARRAY  *dp,
        double  *pt
)
{
        DATARRAY  sd;
        int  asize;
        int  lower, upper;
        register int  i;
        double  x, y0, y1;
                                        /* set up dimensions for recursion */
        if (dp->nd > 1) {
                sd.name = dp->name;
                sd.type = dp->type;
                sd.nd = dp->nd - 1;
                asize = 1;
                for (i = 0; i < sd.nd; i++) {
                        sd.dim[i].org = dp->dim[i+1].org;
                        sd.dim[i].siz = dp->dim[i+1].siz;
                        sd.dim[i].p = dp->dim[i+1].p;
                        asize *= sd.dim[i].ne = dp->dim[i+1].ne;
                }
        }
                                        /* get independent variable */
        if (dp->dim[0].p == NULL) {             /* evenly spaced points */
                x = (pt[0] - dp->dim[0].org)/dp->dim[0].siz;
                x *= (double)(dp->dim[0].ne - 1);
                i = x;
                if (i < 0)
                        i = 0;
                else if (i > dp->dim[0].ne - 2)
                        i = dp->dim[0].ne - 2;
        } else {                                /* unevenly spaced points */
                if (dp->dim[0].siz > 0.0) {
                        lower = 0;
                        upper = dp->dim[0].ne;
                } else {
                        lower = dp->dim[0].ne;
                        upper = 0;
                }
                do {
                        i = (lower + upper) >> 1;
                        if (pt[0] >= dp->dim[0].p[i])
                                lower = i;
                        else
                                upper = i;
                } while (i != (lower + upper) >> 1);
                if (i > dp->dim[0].ne - 2)
                        i = dp->dim[0].ne - 2;
                x = i + (pt[0] - dp->dim[0].p[i]) /
                                (dp->dim[0].p[i+1] - dp->dim[0].p[i]);
        }
                                        /* get dependent variable */
        if (dp->nd > 1) {
                if (dp->type == DATATY) {
                        sd.arr.d = dp->arr.d + i*asize;
                        y0 = datavalue(&sd, pt+1);
                        sd.arr.d = dp->arr.d + (i+1)*asize;
                        y1 = datavalue(&sd, pt+1);
                } else {
                        sd.arr.c = dp->arr.c + i*asize;
                        y0 = datavalue(&sd, pt+1);
                        sd.arr.c = dp->arr.c + (i+1)*asize;
                        y1 = datavalue(&sd, pt+1);
                }
        } else {
                if (dp->type == DATATY) {
                        y0 = dp->arr.d[i];
                        y1 = dp->arr.d[i+1];
                } else {
                        y0 = colrval(dp->arr.c[i],dp->type);
                        y1 = colrval(dp->arr.c[i+1],dp->type);
                }
        }
        /*
         * Extrapolate as far as one division, then
         * taper off harmonically to zero.
         */
        if (x > i+2)
                return( (2*y1-y0)/(x-(i-1)) );

        if (x < i-1)
                return( (2*y0-y1)/(i-x) );

        return( y0*((i+1)-x) + y1*(x-i) );
}
Revision:	2.27
Committed:	Tue Mar 30 16:13:01 2004 UTC (20 years, 1 month ago) by schorsch
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R6
Changes since 2.26:	+21 -14 lines
Log Message:	Continued ANSIfication. There are only bits and pieces left now.
#	User	Rev	Content
1	greg	1.1	#ifndef lint
2	schorsch	2.27	static const char RCSid[] = "$Id: data.c,v 2.26 2004/01/02 11:43:42 schorsch Exp $";
3	greg	1.1	#endif
4			/*
5			* data.c - routines dealing with interpolated data.
6			*/
7
8	greg	2.16	#include "copyright.h"
9	greg	2.22
10			#include <time.h>
11	greg	2.15
12	greg	2.25	#include "platform.h"
13	greg	1.1	#include "standard.h"
14			#include "color.h"
15	greg	1.11	#include "resolu.h"
16	schorsch	2.27	#include "view.h"
17	greg	1.1	#include "data.h"
18
19	greg	2.7	/* picture memory usage before warning */
20			#ifndef PSIZWARN
21	greg	2.18	#ifdef SMLMEM
22			#define PSIZWARN 1500000
23			#else
24	gregl	2.13	#define PSIZWARN 5000000
25	greg	2.7	#endif
26			#endif
27	greg	1.1
28	greg	2.7	#ifndef TABSIZ
29	greg	2.6	#define TABSIZ 97 /* table size (prime) */
30	greg	2.7	#endif
31	greg	2.6
32			#define hash(s) (shash(s)%TABSIZ)
33
34
35			static DATARRAY dtab[TABSIZ]; / data array list */
36	greg	1.1
37	schorsch	2.26	static gethfunc headaspect;
38
39	greg	1.1
40	schorsch	2.27	extern DATARRAY *
41			getdata( /* get data array dname */
42			char *dname
43			)
44	greg	1.1	{
45			char *dfname;
46			FILE *fp;
47			int asize;
48	greg	1.4	register int i, j;
49	greg	1.1	register DATARRAY *dp;
50			/* look for array in list */
51	greg	2.6	for (dp = dtab[hash(dname)]; dp != NULL; dp = dp->next)
52	greg	1.1	if (!strcmp(dname, dp->name))
53			return(dp); /* found! */
54			/*
55			* If we haven't loaded the data already, we will look
56	greg	2.5	* for it in the directories specified by the library path.
57	greg	1.1	*
58			* The file has the following format:
59			*
60	greg	1.4	* N
61	greg	1.1	* beg0 end0 n0
62			* beg1 end1 n1
63			* . . .
64	greg	1.4	* begN endN nN
65	greg	1.1	* data, later dimensions changing faster
66			* . . .
67			*
68	greg	1.4	* For irregularly spaced points, the following can be
69			* substituted for begi endi ni:
70			*
71	greg	1.6	* 0 0 ni p0i p1i .. pni
72	greg	1.1	*/
73
74	greg	2.17	if ((dfname = getpath(dname, getrlibpath(), R_OK)) == NULL) {
75	greg	1.1	sprintf(errmsg, "cannot find data file \"%s\"", dname);
76			error(USER, errmsg);
77			}
78			if ((fp = fopen(dfname, "r")) == NULL) {
79			sprintf(errmsg, "cannot open data file \"%s\"", dfname);
80			error(SYSTEM, errmsg);
81			}
82			/* get dimensions */
83	greg	2.15	if (fgetval(fp, 'i', (char *)&asize) <= 0)
84	greg	1.1	goto scanerr;
85	schorsch	2.24	if ((asize <= 0) \| (asize > MAXDDIM)) {
86	greg	1.1	sprintf(errmsg, "bad number of dimensions for \"%s\"", dname);
87			error(USER, errmsg);
88			}
89	greg	2.12	if ((dp = (DATARRAY *)malloc(sizeof(DATARRAY))) == NULL)
90			goto memerr;
91			dp->name = savestr(dname);
92			dp->type = DATATY;
93			dp->nd = asize;
94	greg	1.1	asize = 1;
95			for (i = 0; i < dp->nd; i++) {
96	greg	2.15	if (fgetval(fp, DATATY, (char *)&dp->dim[i].org) <= 0)
97	greg	1.6	goto scanerr;
98	greg	2.15	if (fgetval(fp, DATATY, (char *)&dp->dim[i].siz) <= 0)
99	greg	1.10	goto scanerr;
100	greg	2.15	if (fgetval(fp, 'i', (char *)&dp->dim[i].ne) <= 0)
101	greg	1.10	goto scanerr;
102	greg	1.6	if (dp->dim[i].ne < 2)
103			goto scanerr;
104			asize *= dp->dim[i].ne;
105			if ((dp->dim[i].siz -= dp->dim[i].org) == 0) {
106	greg	2.12	dp->dim[i].p = (DATATYPE *)
107			malloc(dp->dim[i].ne*sizeof(DATATYPE));
108	greg	1.4	if (dp->dim[i].p == NULL)
109			goto memerr;
110	greg	2.10	for (j = 0; j < dp->dim[i].ne; j++)
111	greg	2.15	if (fgetval(fp, DATATY,
112			(char *)&dp->dim[i].p[j]) <= 0)
113	greg	1.4	goto scanerr;
114			for (j = 1; j < dp->dim[i].ne-1; j++)
115			if ((dp->dim[i].p[j-1] < dp->dim[i].p[j]) !=
116			(dp->dim[i].p[j] < dp->dim[i].p[j+1]))
117			goto scanerr;
118			dp->dim[i].org = dp->dim[i].p[0];
119			dp->dim[i].siz = dp->dim[i].p[dp->dim[i].ne-1]
120			- dp->dim[i].p[0];
121			} else
122	greg	1.6	dp->dim[i].p = NULL;
123	greg	1.1	}
124	greg	2.12	if ((dp->arr.d = (DATATYPE )malloc(asizesizeof(DATATYPE))) == NULL)
125	greg	1.1	goto memerr;
126
127	greg	2.10	for (i = 0; i < asize; i++)
128	greg	2.15	if (fgetval(fp, DATATY, (char *)&dp->arr.d[i]) <= 0)
129	greg	1.1	goto scanerr;
130			fclose(fp);
131	greg	2.6	i = hash(dname);
132			dp->next = dtab[i];
133			return(dtab[i] = dp);
134	greg	1.1
135			memerr:
136			error(SYSTEM, "out of memory in getdata");
137			scanerr:
138			sprintf(errmsg, "%s in data file \"%s\"",
139			feof(fp) ? "unexpected EOF" : "bad format", dfname);
140			error(USER, errmsg);
141	schorsch	2.27	return NULL; /* pro forma return */
142	greg	1.1	}
143
144
145	greg	2.15	static int
146	schorsch	2.26	headaspect( /* check string for aspect ratio */
147			char *s,
148			void *iap
149			)
150	greg	1.5	{
151	gwlarson	2.14	char fmt[32];
152
153	greg	1.5	if (isaspect(s))
154	schorsch	2.26	(double)iap *= aspectval(s);
155	greg	2.15	else if (formatval(fmt, s) && !globmatch(PICFMT, fmt))
156	schorsch	2.26	(double)iap = 0.0;
157	gwlarson	2.14	return(0);
158	greg	1.5	}
159
160
161	schorsch	2.27	extern DATARRAY *
162			getpict( /* get picture pname */
163			char *pname
164			)
165	greg	1.1	{
166	greg	2.4	double inpaspect;
167	greg	1.1	char *pfname;
168			FILE *fp;
169	greg	2.12	COLR *scanin;
170	greg	1.11	int sl, ns;
171	greg	2.3	RESOLU inpres;
172	schorsch	2.21	RREAL loc[2];
173	greg	1.11	int y;
174			register int x, i;
175	greg	1.1	register DATARRAY *pp;
176			/* look for array in list */
177	greg	2.12	for (pp = dtab[hash(pname)]; pp != NULL; pp = pp->next)
178	greg	1.1	if (!strcmp(pname, pp->name))
179			return(pp); /* found! */
180
181	greg	2.17	if ((pfname = getpath(pname, getrlibpath(), R_OK)) == NULL) {
182	greg	1.1	sprintf(errmsg, "cannot find picture file \"%s\"", pname);
183			error(USER, errmsg);
184			}
185	greg	2.12	if ((pp = (DATARRAY )malloc(3sizeof(DATARRAY))) == NULL)
186	greg	1.1	goto memerr;
187
188	greg	2.12	pp[0].name = savestr(pname);
189	greg	1.1
190			if ((fp = fopen(pfname, "r")) == NULL) {
191			sprintf(errmsg, "cannot open picture file \"%s\"", pfname);
192			error(SYSTEM, errmsg);
193			}
194	schorsch	2.19	SET_FILE_BINARY(fp);
195	greg	1.1	/* get dimensions */
196	greg	1.5	inpaspect = 1.0;
197	schorsch	2.26	getheader(fp, headaspect, &inpaspect);
198	gwlarson	2.14	if (inpaspect <= FTINY \|\| !fgetsresolu(&inpres, fp))
199	greg	1.1	goto readerr;
200	greg	2.12	pp[0].nd = 2;
201			pp[0].dim[0].ne = inpres.yr;
202			pp[0].dim[1].ne = inpres.xr;
203			pp[0].dim[0].org =
204			pp[0].dim[1].org = 0.0;
205			if (inpres.xr <= inpres.yr*inpaspect) {
206			pp[0].dim[0].siz = inpaspect *
207			(double)inpres.yr/inpres.xr;
208			pp[0].dim[1].siz = 1.0;
209			} else {
210			pp[0].dim[0].siz = 1.0;
211			pp[0].dim[1].siz = (double)inpres.xr/inpres.yr /
212			inpaspect;
213			}
214			pp[0].dim[0].p = pp[0].dim[1].p = NULL;
215			sl = scanlen(&inpres); /* allocate array */
216			ns = numscans(&inpres);
217			i = nsslsizeof(COLR);
218	greg	2.7	#if PSIZWARN
219	greg	2.12	if (i > PSIZWARN) { /* memory warning */
220	greg	2.7	sprintf(errmsg, "picture file \"%s\" using %d bytes of memory",
221			pname, i);
222			error(WARNING, errmsg);
223			}
224			#endif
225	greg	2.12	if ((pp[0].arr.c = (COLR *)malloc(i)) == NULL)
226			goto memerr;
227	greg	1.1	/* load picture */
228	greg	2.12	if ((scanin = (COLR )malloc(slsizeof(COLR))) == NULL)
229	greg	1.1	goto memerr;
230	greg	1.11	for (y = 0; y < ns; y++) {
231	greg	2.12	if (freadcolrs(scanin, sl, fp) < 0)
232	greg	1.1	goto readerr;
233	greg	1.11	for (x = 0; x < sl; x++) {
234			pix2loc(loc, &inpres, x, y);
235			i = (int)(loc[1]inpres.yr)inpres.xr +
236			(int)(loc[0]*inpres.xr);
237	greg	2.12	copycolr(pp[0].arr.c[i], scanin[x]);
238	greg	1.11	}
239	greg	1.1	}
240	greg	2.15	free((void *)scanin);
241	greg	1.1	fclose(fp);
242	greg	2.6	i = hash(pname);
243	greg	2.12	pp[0].next = dtab[i]; /* link into picture list */
244	schorsch	2.23	pp[1] = pp[0];
245			pp[2] = pp[0];
246	greg	2.12	pp[0].type = RED; /* differentiate RGB records */
247			pp[1].type = GRN;
248			pp[2].type = BLU;
249			return(dtab[i] = pp);
250	greg	1.1
251			memerr:
252			error(SYSTEM, "out of memory in getpict");
253			readerr:
254			sprintf(errmsg, "bad picture file \"%s\"", pfname);
255			error(USER, errmsg);
256	schorsch	2.27	return NULL; /* pro forma return */
257	greg	1.1	}
258
259
260	schorsch	2.27	extern void
261			freedata( /* release data array reference */
262			DATARRAY *dta
263			)
264	greg	1.1	{
265	greg	2.5	DATARRAY head;
266	greg	2.6	int hval, nents;
267	greg	2.15	register DATARRAY dpl, dp;
268	greg	1.4	register int i;
269	greg	1.1
270	greg	2.15	if (dta == NULL) { /* free all if NULL */
271	greg	2.6	hval = 0; nents = TABSIZ;
272			} else {
273	greg	2.15	hval = hash(dta->name); nents = 1;
274	greg	2.6	}
275			while (nents--) {
276			head.next = dtab[hval];
277			dpl = &head;
278			while ((dp = dpl->next) != NULL)
279	schorsch	2.24	if ((dta == NULL) \| (dta == dp)) {
280	greg	2.6	dpl->next = dp->next;
281	greg	2.12	if (dp->type == DATATY)
282	greg	2.15	free((void *)dp->arr.d);
283	greg	2.12	else
284	greg	2.15	free((void *)dp->arr.c);
285	greg	2.6	for (i = 0; i < dp->nd; i++)
286			if (dp->dim[i].p != NULL)
287	greg	2.15	free((void *)dp->dim[i].p);
288	greg	2.6	freestr(dp->name);
289	greg	2.15	free((void *)dp);
290	greg	2.6	} else
291			dpl = dp;
292			dtab[hval++] = head.next;
293			}
294	greg	1.1	}
295
296
297	schorsch	2.27	extern double
298			datavalue( /* interpolate data value at a point */
299			register DATARRAY *dp,
300			double *pt
301			)
302	greg	1.1	{
303			DATARRAY sd;
304			int asize;
305	greg	1.6	int lower, upper;
306	greg	1.1	register int i;
307	greg	2.9	double x, y0, y1;
308	greg	1.4	/* set up dimensions for recursion */
309	greg	2.12	if (dp->nd > 1) {
310			sd.name = dp->name;
311			sd.type = dp->type;
312			sd.nd = dp->nd - 1;
313			asize = 1;
314			for (i = 0; i < sd.nd; i++) {
315			sd.dim[i].org = dp->dim[i+1].org;
316			sd.dim[i].siz = dp->dim[i+1].siz;
317			sd.dim[i].p = dp->dim[i+1].p;
318			asize *= sd.dim[i].ne = dp->dim[i+1].ne;
319			}
320	greg	1.1	}
321	greg	1.4	/* get independent variable */
322			if (dp->dim[0].p == NULL) { /* evenly spaced points */
323			x = (pt[0] - dp->dim[0].org)/dp->dim[0].siz;
324	greg	2.9	x *= (double)(dp->dim[0].ne - 1);
325	greg	1.4	i = x;
326			if (i < 0)
327			i = 0;
328			else if (i > dp->dim[0].ne - 2)
329			i = dp->dim[0].ne - 2;
330			} else { /* unevenly spaced points */
331	greg	1.6	if (dp->dim[0].siz > 0.0) {
332			lower = 0;
333			upper = dp->dim[0].ne;
334			} else {
335			lower = dp->dim[0].ne;
336			upper = 0;
337			}
338			do {
339			i = (lower + upper) >> 1;
340			if (pt[0] >= dp->dim[0].p[i])
341			lower = i;
342	greg	1.8	else
343	greg	1.6	upper = i;
344			} while (i != (lower + upper) >> 1);
345	greg	1.8	if (i > dp->dim[0].ne - 2)
346	greg	1.4	i = dp->dim[0].ne - 2;
347			x = i + (pt[0] - dp->dim[0].p[i]) /
348			(dp->dim[0].p[i+1] - dp->dim[0].p[i]);
349			}
350			/* get dependent variable */
351	greg	2.12	if (dp->nd > 1) {
352			if (dp->type == DATATY) {
353			sd.arr.d = dp->arr.d + i*asize;
354			y0 = datavalue(&sd, pt+1);
355			sd.arr.d = dp->arr.d + (i+1)*asize;
356			y1 = datavalue(&sd, pt+1);
357			} else {
358			sd.arr.c = dp->arr.c + i*asize;
359			y0 = datavalue(&sd, pt+1);
360			sd.arr.c = dp->arr.c + (i+1)*asize;
361			y1 = datavalue(&sd, pt+1);
362			}
363	greg	1.1	} else {
364	greg	2.12	if (dp->type == DATATY) {
365			y0 = dp->arr.d[i];
366			y1 = dp->arr.d[i+1];
367			} else {
368			y0 = colrval(dp->arr.c[i],dp->type);
369			y1 = colrval(dp->arr.c[i+1],dp->type);
370			}
371	greg	1.1	}
372			/*
373			* Extrapolate as far as one division, then
374			* taper off harmonically to zero.
375			*/
376			if (x > i+2)
377	greg	2.9	return( (2*y1-y0)/(x-(i-1)) );
378	greg	1.1
379	greg	2.9	if (x < i-1)
380			return( (2*y0-y1)/(i-x) );
381
382			return( y0((i+1)-x) + y1(x-i) );
383	greg	1.1	}