/**--------------------------------------------------------------------------- ** ** db.c -- Access CTD data from a CODAS database ** ** Author : Pierre Jaccard ** Created On : 1999/07/15 16:47:03 ** Last Modified By: Pierre Jaccard ** Last Modified On: 1999/07/16 20:06:36 ** Update Count : 2 ** Directory : /home/pego/pcd1/codas3c/gfi/src/libs/ctd/ ** Version : 0.0 ** Status : Unknown ** ---------------------------------------------------------------------- ** ** DESCRIPTION: ** ** These functions are used to access various CTD data from a CODAS ** database. ** ** ---------------------------------------------------------------------- ** ** REVISIONS: ** ---------------------------------------------------------------------- ** ** CHANGES: **------------------------------------------------------------------------**/ #include "db.h" /* ------------------------------------------------------------------ This function gets a profile of CTD data from current database pointer. It is an exact copy of the function get_ctd_profile used by adcpsect. ------------------------------------------------------------------ */ #if PROTOTYPE_ALLOWED void get_ctd_prf(/* Place for CTD data */ CTD_PROFILE_TYPE *prof) #else void get_ctd_prf(prof) CTD_PROFILE_TYPE *prof; #endif { double sigma; /* dummy used in SVAN */ double theta; int step = 1; int ngaps = 0; /* max number of interpolations done */ int ierr; int n, ng; int i; get_latlon(&(prof->position)); check_dbget(TIME, (char *) &(prof->time), sizeof(prof->time), "DBGET, time"); prof->n = (int) check_dbget_f(P, prof->pressure, NPMAX, "DBGET_F, pressure"); n = (int) check_dbget_f(TEMPERATURE, prof->temperature, NPMAX, "DBGET_F, temperature"); prof->n = min_val(prof->n, n); n = (int) check_dbget_f(SALINITY, prof->salinity, NPMAX, "DBGET_F, salinity"); prof->n = min_val(prof->n, n); /* It is assumed that the CTD data are nearly perfect, so this gap filling will only occasionally be called into play, and only for small gaps. */ ng = fill_gaps(prof->salinity, prof->n); ngaps = ng; ng = fill_gaps(prof->temperature, prof->n); ngaps = max_val(ngaps, ng); ng = fill_gaps(prof->pressure, prof->n); ngaps = max_val(ngaps, ng); if (ngaps == prof->n) prof->n = 0; /* don't try to use this profile */ for (i=0; i < prof->n; i++) { prof->depth[i] = (float) p_depth( prof->pressure[i], prof->position.lat); prof->svel[i] = (float) SVEL( prof->salinity[i], prof->temperature[i], prof->pressure[i]); switch (prof->density_var) { case CTD_SVAN: prof->sigma_sva[i] = (float) SVAN( prof->salinity[i], prof->temperature[i], prof->pressure[i], &sigma); break; case CTD_SIGMA_THETA: theta = THETA(prof->salinity[i], prof->temperature[i], 0.0, prof->pressure[i]); (void) SVAN( prof->salinity[i], theta, 0.0, &sigma); prof->sigma_sva[i] = (float) sigma; break; case CTD_POT_SVAN: theta = THETA(prof->salinity[i], prof->temperature[i], 0.0, prof->pressure[i]); prof->sigma_sva[i] = (float) SVAN( prof->salinity[i], theta, 0.0, &sigma); break; case CTD_SIGMA_T: (void) SVAN( prof->salinity[i], prof->temperature[i], 0.0, &sigma); prof->sigma_sva[i] = (float) sigma; break; case CTD_NONE: prof->sigma_sva[i] = BADFLOAT; break; default: printf("\n%d is an invalid density variable specification\n", prof->density_var); exit(-1); } } if (prof->n == 0) /* try the next one */ { printf("\nBad CTD profile."); write_ymdhms_time(stdout, &(prof->time)); printf(" position: %f %f\n", prof->position.lat, prof->position.lon); DBMOVE(&step, &ierr); check_error(ierr, "DBMOVE in get_ctd_prf"); get_ctd_prf(prof); /* recursive call */ } return; /* only exit */ } /* get_ctd_profile */ /* ------------------------------------------------------------------ Given a depth in meters, this function returns the interpolated temperature at this depth. Interpolation method used is linear interpolation. RETURNS: BADFLOAT on error. ------------------------------------------------------------------ */ #if PROTOTYPE_ALLOWED FLOAT get_ctd_temp(/* Pointer to CTD data */ CTD_PROFILE_TYPE *ctd, /* Interpolation depth */ FLOAT depth) #else FLOAT get_ctd_temp(ctd, depth) #endif { float p1, p2, t1, t2; int i, done; /* Parses the data in the CTD array */ i = done = 0; while(!done){ /* Loop exit flag */ done = !((ctd->pressure[i] < depth) && (ctd->temperature[i] < ADJ_BADFLOAT) && (i<(ctd->n))); /* Keep previous good data */ if((ctd->temperature[i] < ADJ_BADFLOAT) && !done){ t1 = ctd->temperature[i]; p1 = ctd->pressure[i]; } i++; } i--; if(error_found(i==0, "Specified depth too shallow")) return(BADFLOAT); if(error_found(i==NPMAX, "No temperature for specified depth")) return(BADFLOAT); p2 = ctd->pressure[i]; t2 = ctd->temperature[i]; return((FLOAT) t1 + (t2-t1)*(depth-p1)/(p2-p1)); } /* ------------------------------------------------------------------ Given a depth in meters, this function returns the interpolated salinity at this depth. Interpolation method used is linear interpolation. RETURNS: BADFLOAT on error. ------------------------------------------------------------------ */ #if PROTOTYPE_ALLOWED FLOAT get_ctd_sal(/* Pointer to CTD data */ CTD_PROFILE_TYPE *ctd, /* Interpolation depth */ FLOAT depth) #else FLOAT get_ctd_sal(ctd, depth) #endif { float p1, p2, s1, s2; int i, done; /* Parses the data in the CTD array */ i = done = 0; while(!done){ /* Loop exit flag */ done = !((ctd->pressure[i] < depth) && (ctd->salinity[i] < ADJ_BADFLOAT) && (i<(ctd->n))); /* Keep previous good data */ if((ctd->salinity[i] < ADJ_BADFLOAT) && !done){ s1 = ctd->salinity[i]; p1 = ctd->pressure[i]; } i++; } i--; if(error_found(i==0, "Specified depth too shallow")) return(BADFLOAT); if(error_found(i==NPMAX, "No salinity for specified depth")) return(BADFLOAT); p2 = ctd->pressure[i]; s2 = ctd->salinity[i]; return((FLOAT) s1 + (s2-s1)*(depth-p1)/(p2-p1)); }