diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7fb56d3c..3f8c42c5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,7 +16,7 @@ option(USE_HDF5 "Use HDF5?" off)
 option(USE_REGEX "Use Regex?" on)
 option(USE_TIGGE "Use tigge?" on)
 option(USE_MYSQL "Use MySQL?" off)
-option(USE_IPOLATES "iplib=0,1,3?" 3)
+option(USE_IPOLATES "Use Ipolates" on)
 option(USE_UDF "Use UDF?" off)
 option(USE_OPENMP "Use OpenMP?" on)
 option(USE_PROJ4 "Use Proj4?" off)
@@ -83,17 +83,15 @@ endif()
 
 # If user wants to use NCEPLIBS-ip, find it and the sp library.
 message(STATUS "Checking if the user want to use NCEPLIBS-ip...")
-if(USE_IPOLATES EQUAL 1)
+if(USE_IPOLATES)
   find_package(ip CONFIG REQUIRED)
-  find_package(sp CONFIG REQUIRED)
-elseif(USE_IPOLATES EQUAL 3)
-  find_package(ip2 CONFIG REQUIRED)
+  list(APPEND definitions_list -DIPOLATES_LIB="ipolates_lib_d")
 endif()
 
-if(NOT USE_IPOLATES EQUAL 0)
-  list(APPEND definitions_list -DIPOLATES_LIB="ipolates_lib")
-endif()
-list(APPEND definitions_list -DUSE_IPOLATES=${USE_IPOLATES})
+# if(NOT USE_IPOLATES EQUAL 0)
+#   list(APPEND definitions_list -DIPOLATES_LIB="ipolates_lib")
+# endif()
+# list(APPEND definitions_list -DUSE_IPOLATES=${USE_IPOLATES})
 
 message(STATUS "Checking if the user want to use NetCDF...")
 if(USE_NETCDF4)
diff --git a/wgrib2/CMakeLists.txt b/wgrib2/CMakeLists.txt
index e0508874..34734269 100644
--- a/wgrib2/CMakeLists.txt
+++ b/wgrib2/CMakeLists.txt
@@ -24,7 +24,7 @@ Import_grib_fs.c Import_lonlat.c Import_netcdf.c init.c int8.c
 intpower.c Inv.c Inv_no.c Irr_grids.c itoshort_a.c JMA.c jpeg_pk.c
 Last.c lat2ij.c Latlon.c Level.c Limit.c Lola.c Lvl.c Macro.c
 manage_inv_out.c Match.c Match_fs.c Match_inv.c Mem_buffer.c Merge.c
-Misc.c missing.c mk_gdt.c mk_kgds.c Model_version_date.c Mod_grib.c
+Misc.c missing.c mk_gdt.c Model_version_date.c Mod_grib.c
 Mysql.c Mysql_dump.c Mysql_speed.c Names.c ncep_grids.c NCEP_norm.c
 NCEP_uv.c Ncpu.c Ndate.c Ndates.c Netcdf.c Netcdf_sup.c New_grid.c
 new_grid_lambertc.c New_grid_order.c openmp_util.c parse_loop.c
@@ -105,9 +105,8 @@ endif()
 if(USE_G2CLIB)
 endif()
 
-if(USE_IPOLATES EQUAL 1)
+if(USE_IPOLATES)
   target_link_libraries(obj_lib PUBLIC ip::ip_d)
-  target_link_libraries(obj_lib PUBLIC sp::sp_d)
 
   # Link to the Fortran runtime library for each compiler if using ip2.
   # The wgrib2 exectuable is created using the C compiler and
diff --git a/wgrib2/Config.c b/wgrib2/Config.c
index 7e55577b..d484fb42 100644
--- a/wgrib2/Config.c
+++ b/wgrib2/Config.c
@@ -89,13 +89,9 @@ int f_config(ARG0) {
     strcat(inv_out, "tigge package is not installed\n");
 #endif
 
-#if USE_IPOLATES > 0
+#ifdef USE_IPOLATES
     inv_out += strlen(inv_out);
-    sprintf(inv_out, "IPOLATES " IPOLATES_LIB " (option %d) is installed", USE_IPOLATES);
-#if USE_SPECTRAL > 0
-    strcat(inv_out, " with spectral interpolation");
-#endif
-    strcat(inv_out, ", default vectors:\n");
+    sprintf(inv_out, "IPOLATES NCEPLIBS-ip\n");
 #else
     strcat(inv_out, "interpolation package is not installed, default vectors:\n");
 #endif
diff --git a/wgrib2/New_grid.c b/wgrib2/New_grid.c
index 8247dea3..1fcbbf5e 100644
--- a/wgrib2/New_grid.c
+++ b/wgrib2/New_grid.c
@@ -32,6 +32,8 @@
  *              this makes dlon only xxx.xx precision whic is less
  *              than grib1 (xxx.xxx) and grib2 (xxx.xxxxxx) expectations
  *              should not use float version of ip2.
+ * 4/2024  changed to current ip lib
+ *         removed calls to old ip lib (1)
  */
 
 const char **vectors;
@@ -47,6 +49,8 @@ enum new_grid_format_type new_grid_format;
 static const char *no_vectors[] = { NULL };
 static const char *UV_vectors[] = { "UGRD", "VGRD", NULL };
 
+#ifdef USE_IPOLATES
+
 /*
  * HEADER:111:new_grid_vectors:misc:1:change fields to vector interpolate: X=none,default,UGRD:VGRD,(U:V list)
  */
@@ -122,617 +126,15 @@ int f_new_grid_vectors(ARG1) {
     return 0;
 }
 
-#if USE_IPOLATES == 1
-
-/* This is the grib1 version which is now frozen.
- * The grib2 version is similar but
- *  (1) uses the grib2 version of ipolates
- *  (2) double precision
- *  (3) spectral support was removed
- */
-
-#ifndef _IPOLATES_H
-#define _IPOLATES_H
-#include "ipolates.h"
-#endif
-
-extern unsigned int npnts;
-extern int nx,ny;
-extern double *lat, *lon;
-extern int decode, latlon, file_append, flush_mode;
-extern int use_scale, dec_scale, bin_scale, wanted_bits, max_bits;
-extern enum output_grib_type grib_type;
-extern enum output_order_type output_order;
-extern int save_translation;
-extern enum output_order_type output_order_wanted, output_order;
-
-static int interpol_type = 0;
-static int ipopt[20] = {-1,-1,0, 0,0,0, 0,0,0, 0};
-
-/*
- * HEADER:111:new_grid_interpolation:misc:1:new_grid interpolation X=bilinear,bicubic,neighbor,budget,neighbor-budget
- */
-
-int f_new_grid_interpolation(ARG1) {
-
-   if (strcmp(arg1,"bilinear") == 0) { interpol_type = 0; ipopt[0] = -1; }
-   else if (strcmp(arg1,"bicubic") == 0) { interpol_type = 1; ipopt[0] = 0; }
-   else if (strcmp(arg1,"neighbor") == 0) { interpol_type = 2; ipopt[0] = 1; }
-   else if (strcmp(arg1,"budget") == 0) { interpol_type = 3; ipopt[0] = -1; }
-//  turned off spectral -- new library rarely used interpolation option
-//   else if (strcmp(arg1,"spectral") == 0) { interpol_type = 4; ipopt[0] = 0; ipopt[1] = -1; }
-//  turned off neighbor-budget - save space for rarely used interpolation option
-//   else if (strcmp(arg1,"neighbor-budget") == 0) { interpol_type = 6; ipopt[0] = -1; }
-   else fatal_error("new_grid_interpolation: unknown type %s", arg1);
-
-   return 0;
-}
-
-/*
- * HEADER:111:new_grid_ipopt:misc:1:new_grid ipopt values X=i1:i2..:iN N <= 20
- */
-int f_new_grid_ipopt(ARG1) {
-    int i, k, val, m;
-
-    i = 0;
-    k = sscanf(arg1, "%d%n", &val, &m);
-    while (k == 1) {
-        if (i > 19) fatal_error("new_grid_ipopt: too many ipopt values, 20 max","");
-        ipopt[i++] = val;
-        arg1 += m;
-        k = sscanf(arg1, ":%d%n", &val, &m);
-    }
-    return 0;
-}
-
-/*
- * HEADER:111:new_grid_format:misc:1:new_grid output format  X=bin,ieee,grib
- */
-
-
-int f_new_grid_format(ARG1) {
-    if (mode == -1) {
-	if (strcmp(arg1,"grib") != 0) {
-	    fatal_error("new_grid_format: for IPOLATES=iplib, only grib is supported","");
-	}
-    }
-    return 0;
-}
-
-/*
- * HEADER:111:new_grid_winds:misc:1:new_grid wind orientation: X = grid, earth (no default)
- */
-
-enum wind_rotation_type wind_rotation;
-
-int f_new_grid_winds(ARG1) {
-    int *save;
-    if (mode == -2) {
-	free(*local);
-	return 0;
-    }
-    if (mode == -1) {
-	if ((*local = save = (int *) malloc(sizeof(int))) == NULL) fatal_error("new_grid_winds: malloc","");
-	if (strcmp(arg1,"grid") == 0) *save = 0;
-	else if (strcmp(arg1,"earth") == 0) *save = 1;
-        else fatal_error("new_grid_winds: bad arg %s", arg1);
-    }
-    save = (int *) *local;
-    wind_rotation = (*save) ? earth : grid;
-    return 0;
-}
-
-struct local_struct {
-	// U data
-        float *u_val;
-        int has_u, nx, ny;
-        unsigned char *clone_sec[9];
-        char name[NAMELEN];
-
-	// interpolation
-        int npnts_out;		// must be integer .. fortran call requires int
-        float *rlat, *rlon, *crot, *srot;
-        unsigned char *sec3;
-	int kgds_out[200];
-	double radius_major, radius_minor;
-
-	// output file
-        struct seq_file out;
-};
-
-unsigned char blank_sec1[21] = { 0,0,0,21,1,
-		255,255,255,255,	// center subcenter
-		2,1,255,		// grib master table, local table, sig ref time
-		255, 255, 		// year
-		255, 255, 255, 255, 255, // month .. second
-		255, 255};
-
-/*
- * HEADER:111:new_grid:output:4:bilinear interpolate: X=projection Y=x0:nx:dx Z=y0:ny:dy A=grib_file alpha
- */
-
-int f_new_grid(ARG4) {
-    struct local_struct *save;
-
-    unsigned int i;
-    int is_u, is_v, ftn_npnts, ftn_nout;
-    int kgds[200], km;
-    float *data_in, *data_out;
-    double x0, y0, dx, dy, xn, yn;
-    double lov, lad, latin1, latin2;
-    int proj;					// projection: for LC 0 = NP, 128 = SP
-    char name[NAMELEN];
-    int j, ibi, ibo, iret, nnx, nny, n_out;
-    unsigned char *new_sec[8], *s, *bitmap, *bitmap_out, *p;
-
-    /* for lambertc */
-    double r_maj, r_min, ref_lon, ref_lat;
-
-    if (mode == -1) {			// initialization
-        decode = 1;
-        output_order_wanted = raw;	// in raw order
-
-
-#ifdef G95
-	// initialize g95 runtime library
-	if (g95_runstop == 0) { g95_runtime_start(0,NULL); g95_runstop = 1; }
-#endif
-
-//        if ( (sizeof(vectors) / sizeof (vectors[0])) % 2 == 1) fatal_error("new_grid: program error in vectors[]","");
-
-	// allocate static variables
-
-        *local = save = (struct local_struct *) malloc( sizeof(struct local_struct));
-        if (save == NULL) fatal_error("new_grid: memory allocation error","");
-
-        if (fopen_file(&(save->out), arg4, file_append ? "ab" : "wb") != 0) {
-	    fatal_error("-new_grid: could not open file %s", arg4);
-	}
-
-	save->has_u = 0;
-	save->radius_major = save->radius_minor = 0.0;
-	init_sec(save->clone_sec);
-	s = NULL;
-
-	// parse NCEP grids */
-	ncep_grids(&arg1, &arg2, &arg3);
-
-	// for each output grid
-        if (strcmp(arg1,"latlon") == 0) {
-            if (sscanf(arg2,"%lf:%d:%lf", &x0, &nnx, &dx) != 3)
-                fatal_error("new_grid: XDEF wrong:%s",arg2);
-            if (sscanf(arg3,"%lf:%d:%lf", &y0, &nny, &dy) != 3)
-                fatal_error("new_grid: YDEF wrong:%s",arg3);
-
-	    if (x0 < 0.0) x0 += 360.0;
-            save->nx = nnx;
-            save->ny = nny;
-            save->npnts_out = n_out = nnx*nny;
-            if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-
-            // make a new section 3
-            s = sec3_lola(nnx, x0, dx, nny, y0, dy, sec);
-	}
-        else if (strcmp(arg1,"rot-latlon") == 0) {
-            if (sscanf(arg2,"%lf:%d:%lf", &x0, &nnx, &dx) != 3)
-                fatal_error("new_grid: XDEF wrong:%s",arg2);
-            if (sscanf(arg3,"%lf:%d:%lf", &y0, &nny, &dy) != 3)
-                fatal_error("new_grid: YDEF wrong:%s",arg3);
-
-            if (x0 < 0.0) x0 += 360.0;
-            save->nx = nnx;
-            save->ny = nny;
-            save->npnts_out = n_out = nnx*nny;
-            if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-
-            // make a new section 3
-            s = sec3_lola(nnx, x0, dx, nny, y0, dy, sec);
-        }
-
-
-        else if (strncmp(arg1,"mercator:",9) == 0) {
-            if (sscanf(arg1,"mercator:%lf",  &lad) != 1) 
-                fatal_error("new_grid: LaD (latitude interesection) not specified","");
-            if (sscanf(arg2,"%lf:%d:%lf:%lf", &x0, &nnx, &dx, &xn) != 4)
-                fatal_error("new_grid: XDEF wrong:%s",arg2);
-            if (sscanf(arg3,"%lf:%d:%lf:%lf", &y0, &nny, &dy, &yn) != 4)
-
-	    if (x0 < 0.0) x0 += 360.0;
-            save->nx = nnx;
-            save->ny = nny;
-            save->npnts_out = n_out = nnx*nny;
-            if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-
-            // make a new section 3
-            s = sec3_mercator(lad, nnx, x0, dx, xn, nny, y0, dy, yn, sec);
-	}
-        else if (strcmp(arg1,"gaussian") == 0) {
-            if (sscanf(arg2,"%lf:%d:%lf", &x0, &nnx, &dx) != 3)
-                fatal_error("new_grid: XDEF wrong:%s",arg2);
-            if (sscanf(arg3,"%lf:%d", &y0, &nny) != 2)
-                fatal_error("new_grid: YDEF wrong:%s",arg3);
-
-	    if (x0 < 0.0) x0 += 360.0;
-            save->nx = nnx;
-            save->ny = nny;
-            save->npnts_out = n_out = nnx*nny;
-            if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-            // make a new section 3
-            s = sec3_gaussian(nnx, x0, dx, nny, y0, sec);
-	}
-        else if (strncmp(arg1,"lambert:",8) == 0) {
-            i = sscanf(arg1,"lambert:%lf:%lf:%lf:%lf", &lov, &latin1, &latin2, &lad);
-            if (i < 2) fatal_error("new_grid: arg1 wrong:%s",arg1);
-            if (lov < 0.0)  lov += 360.0;
-            if (i < 3) latin2 = latin1;
-            if (i < 4) lad = latin2;
-            proj = 0;
-            if (latin2 < 0.0) proj = 128;
-
-            if (sscanf(arg2,"%lf:%d:%lf", &x0, &nnx, &dx) != 3)
-                fatal_error("new_grid: XDEF wrong:%s",arg2);
-            if (sscanf(arg3,"%lf:%d:%lf", &y0, &nny, &dy) != 3)
-                fatal_error("new_grid: YDEF wrong:%s",arg3);
-
-	    if (x0 < 0.0) x0 += 360.0;
-            save->nx = nnx;
-            save->ny = nny;
-            save->npnts_out = n_out = nnx*nny;
-            if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-
-            // make a new section 3
-            s = sec3_lc(lov, lad, latin1, latin2, proj, nnx, x0, dx, nny, y0, dy, sec);
-        }
-
-	/* for lambertc, input is the lon-lat of center point */
-	/* can not calc grid until radius is given, so do lambert code to check args */
-
-        else if (strncmp(arg1,"lambertc:",9) == 0) {
-            i = sscanf(arg1,"lambertc:%lf:%lf:%lf:%lf", &lov, &latin1, &latin2, &lad);
-            if (i < 2) fatal_error("new_grid: arg1 wrong:%s",arg1);
-            if (lov < 0.0)  lov += 360.0;
-            if (i < 3) latin2 = latin1;
-            if (i < 4) lad = latin2;
-            proj = 0;
-            if (latin2 < 0.0) proj = 128;
-
-            if (sscanf(arg2,"%lf:%d:%lf", &x0, &nnx, &dx) != 3)
-                fatal_error("new_grid: XDEF wrong:%s",arg2);
-            if (sscanf(arg3,"%lf:%d:%lf", &y0, &nny, &dy) != 3)
-                fatal_error("new_grid: YDEF wrong:%s",arg3);
-
-            if (x0 < 0.0) x0 += 360.0;
-            save->nx = nnx;
-            save->ny = nny;
-            save->npnts_out = n_out = nnx*nny;
-            if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-
-            // make a new section 3
-            s = sec3_lc(lov, lad, latin1, latin2, proj, nnx, x0, dx, nny, y0, dy, sec);
-        }
-
-        else if (strncmp(arg1,"nps:",4) == 0 || strncmp(arg1,"sps:",4) == 0)  {
-            if (sscanf(arg1,"%*[ns]ps:%lf:%lf", &lov, &lad) != 2) fatal_error("new_grid: arg1 wrong:%s",arg1);
-	    if (lad != 60.0) fatal_error("New_grid: only LatD = 60 is supported","");
-            proj = 0;
-	    if (arg1[0] == 's') proj = 128;
-            if (sscanf(arg2,"%lf:%d:%lf", &x0, &nnx, &dx) != 3)
-                fatal_error("new_grid: XDEF wrong:%s",arg2);
-            if (sscanf(arg3,"%lf:%d:%lf", &y0, &nny, &dy) != 3)
-                fatal_error("new_grid: YDEF wrong:%s",arg3);
-	    if (lov < 0.0)  lov += 360.0;
-
-	    if (x0 < 0.0) x0 += 360.0;
-            save->nx = nnx;
-            save->ny = nny;
-            save->npnts_out = n_out = nnx*nny;
-            if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-
-            // make a new section 3
-	    s = sec3_polar_stereo(lov, lad, proj, nnx, x0, dx, nny, y0, dy, sec);
-	}
-        else fatal_error("new_grid: unsupported output grid %s", arg1);
-
-	new_sec[1] = blank_sec1;	// add center info
-	// save new section 3
-        i = (int) uint4(s);         // size of section 3
-        new_sec[3] = save->sec3 = (unsigned char *) malloc(i * sizeof(unsigned char));
-        for (j = 0; j < i; j++) save->sec3[j] = s[j];
-
-	// apply wind rotation .. change flag 3.3
-	if (wind_rotation == undefined && strncmp(arg1,"grib",4) != 0) {
-	    fprintf(stderr,"Warning: -new_grid wind orientation undefined, "
-                "use \"-new_grid_winds (grid|earth)\", earth used\n");
-            wind_rotation = earth;
-	}
-	if ((p = flag_table_3_3_location(new_sec)) != NULL) {
-	    if (wind_rotation == grid) *p = *p | 8;
-	    else if (wind_rotation == earth) *p = *p & (255 - 8);
-	}
-
-        if (mk_kgds(new_sec, save->kgds_out)) fatal_error("new_grid: encoding output kgds","");
-
-	/* some vectors need by interpolation routines */
-        if ((save->rlat = (float *) malloc( sizeof(float) * (size_t) n_out)) == NULL)
-                fatal_error("new_grid memory allocation","");
-        if ((save->rlon = (float *) malloc(sizeof(float) * (size_t) n_out)) == NULL)
-                fatal_error("new_grid memory allocation","");
-        if ((save->crot = (float *) malloc(sizeof(float) * (size_t) n_out)) == NULL)
-                fatal_error("new_grid memory allocation","");
-        if ((save->srot = (float *) malloc(sizeof(float) * (size_t) n_out)) == NULL)
-                fatal_error("new_grid memory allocation","");
-
-	return 0;
-    }
-
-    save = (struct local_struct *) *local;
-
-    if (mode == -2) {			// cleanup
-#ifdef G95
-	if (g95_runstop == 1) { g95_runtime_stop(); g95_runstop = 0; }
-#endif
-	if (save->has_u > 0) {
-	    fprintf(stderr,"-new_grid: last field %s was not interpolated (missing V)\n", save->name);
-	    free(save->u_val);
-	    free_sec(save->clone_sec);
-	}
-	free(save->rlon);
-	free(save->rlat);
-	free(save->crot);
-	free(save->srot);
-	free(save->sec3);
-	fclose_file(&(save->out));
-	free(save);
-
-	return 0;
-    }
-
-    if (mode >= 0) {			// processing
-
-	/* The kgds of some output grids will change depending on input grid */
-	/* for example, radius of earth is not known grib file is read, */
-	/*   and mass vs wind fields */
-	/* right nowm, only affects lambertc */
-
-        if (strncmp(arg1,"lambertc:",8) == 0) {
-
-	    // lambertc depends on the radius of the earth which is
-            // set by the input grib file
-
-	    /* read earth radius */
-	    i = axes_earth(sec, &r_maj, &r_min, NULL);
-	    if (i) fatal_error_i("axes_earth: error code %d", i);
-
-	    if (save->radius_major != r_maj || save->radius_minor != r_min) {
-
-		// update sec3 and kgds
-
-                i = sscanf(arg1,"lambertc:%lf:%lf:%lf:%lf", &lov, &latin1, &latin2, &lad);
-                if (i < 2) fatal_error("new_grid: arg1 wrong:%s",arg1);
-                if (lov < 0.0)  lov += 360.0;
-                if (i < 3) latin2 = latin1;
-                if (i < 4) lad = latin2;
-                proj = 0;
-                if (latin2 < 0.0) proj = 128;
-
-                if (sscanf(arg2,"%lf:%d:%lf", &x0, &nnx, &dx) != 3)
-                    fatal_error("new_grid: XDEF wrong:%s",arg2);
-                if (sscanf(arg3,"%lf:%d:%lf", &y0, &nny, &dy) != 3)
-                    fatal_error("new_grid: YDEF wrong:%s",arg3);
-
-                if (x0 < 0.0) x0 += 360.0;
-                save->nx = nnx;
-                save->ny = nny;
-                save->npnts_out = n_out = nnx*nny;
-                if (n_out <= 0) fatal_error("new_grid: bad nx, ny","");
-
-	        ref_lon = x0;
-	        ref_lat = y0;
- 
-	        i = new_grid_lambertc(nnx, nny, ref_lon, ref_lat, latin1, latin2, lov, lad, r_maj, r_min, dx, dy, &x0, &y0);
-	        if (i) fatal_error_i("new_grid_lambertc: error code %d", i);
-
-                // make a new section 3
-                s = sec3_lc(lov, lad, latin1, latin2, proj, nnx, x0, dx, nny, y0, dy, sec);
-
-	        // save new section 3
-                i = (int) uint4(s);         // size of section 3
-                for (j = 0; j < i; j++) save->sec3[j] = s[j];
-
-	        // make kgds
-		new_sec[1] = blank_sec1;	// add center info
-	        new_sec[3] = save->sec3;
-                if (mk_kgds(new_sec, save->kgds_out)) fatal_error("new_grid: encoding output kgds","");
-
-	        // save radius of earth, to show sec3 and kgds has been done
-	        save->radius_major = r_maj;
-	        save->radius_minor = r_min;
-	    }
-        }
-
-	if (output_order != raw) fatal_error("new_grid: must be in raw output order","");
-        i = getName(sec, mode, NULL, name, NULL, NULL);
-	is_u = is_v = 0;
-//	for (j = 0 ; j < sizeof(vectors) / sizeof(vectors[0]); j++) {
-	for (j = 0; vectors[j] != NULL; j++) {
-	    if (strcmp(name,vectors[j]) == 0) {
-		if (j % 2 == 0) is_u = 1;
-		else is_v = 1;
-		break;
-	    }
-	}
-
-// fprintf(stderr, " %s isu %d isv %d has_u %d\n", name, is_u, is_v, save->has_u);
-//  for (i = 0; i < 12; i++) { printf("kgds_out[%d] = %d ",i,save->kgds_out[i]); }
-
-	// check if V matches expectation
-
-	if (is_v && (save->has_u == 0  || (same_sec0(sec,save->clone_sec) != 1 ||
-            same_sec1(sec,save->clone_sec) != 1 ||
-            same_sec3(sec,save->clone_sec) != 1 ||
-            same_sec4(sec,save->clone_sec) != 1) )) {
-	    fprintf(stderr,"-new_grid: %s doesn't pair with previous vector field, field ignored\n", name);
-	    return 0;
-	}
-
-	// if U field - save
-
-        if (is_u) {
-            if (save->has_u > 0) {
-                fprintf(stderr,"-new_grid: missing V, %s not interpolated\n",save->name);
-                free(save->u_val);
-                free_sec(save->clone_sec);
-            }
-            copy_sec(sec, save->clone_sec);
-            copy_data(data,ndata,&(save->u_val));
-            GB2_ParmNum(save->clone_sec) = GB2_ParmNum(sec) + 1;
-            save->has_u = 1;
-	    strncpy(save->name, name,NAMELEN-1);
-	    save->name[NAMELEN-2]=0;
-            return 0;
-        }
-
-	// at this point will call polates with either a scalar or vector
-
-	n_out = save->npnts_out;
-	nnx = save->nx;
-	nny = save->ny;
-	km = 1;			// only one field
-
-	if (mk_kgds(sec, kgds)) fatal_error("new_grid: encoding input kgds","");
-
-	data_in = (float *) malloc((1 + (is_v != 0)) * sizeof(float) * (size_t) npnts);
-        bitmap = (unsigned char *) malloc(sizeof(unsigned char) * (size_t) npnts);
-        bitmap_out = (unsigned char *) malloc(sizeof(unsigned char) * (size_t) n_out);
-	data_out = (float *) malloc((1 + (is_v != 0)) * sizeof(float) * (size_t) n_out);
-
-	if (data_in == NULL || data_out == NULL || bitmap == NULL || bitmap_out == NULL) 
-	    fatal_error("new_grid: memory allocation problem","");
-
-	if (is_v) {
-#pragma omp parallel for private(i)
-	    for (i = 0; i < npnts; i++) {
-                if (DEFINED_VAL(data[i]) && DEFINED_VAL(save->u_val[i])) {
-                    data_in[i] = save->u_val[i];
-                    data_in[i+npnts] = data[i];
-                    bitmap[i] = 1;
-		}
-		else {
-                    data_in[i] = data_in[i + npnts] = 0.0;
-                    bitmap[i] = 0;
-		}
-	    }
-	    if (mode == 98) fprintf(stderr," UV interpolation %s , %s\n", save->name, name);
-	}
-	else {
-#pragma omp parallel for private(i)
-	    for (i = 0; i < npnts; i++) {
-                if (DEFINED_VAL(data[i])) {
-                    data_in[i] = data[i];
-                    bitmap[i] = 1;
-		}
-		else {
-                    data_in[i] = 0.0;
-                    bitmap[i] = 0;
-		}
-	    }
-	}
-	// check if bitmap is used
-	ibi = 0;                        // input bitmap is not used
-	for (i = 0; i < npnts; i++) {
-	    if (bitmap[i] == 0) {
-		ibi = 1;
-		break;
-	    }
-	}
-	// interpolate
-
-// for (i = 0; i < 12; i++) { printf("\nkgds_in[%d] = %d  out=%d ",i,kgds[i],save->kgds_out[i]); }
-	ftn_npnts = (int) npnts;
-	ftn_nout = (int) n_out;
-	if (is_v) {
-	    IPOLATEV(&interpol_type, ipopt,kgds,save->kgds_out, 
-		&ftn_npnts, &n_out, &km, &ibi, bitmap, data_in, data_in+npnts, 
-		&ftn_nout,save->rlat,save->rlon, save->crot, save->srot,
-                &ibo, bitmap_out, data_out, data_out + n_out, &iret);
-	}
-	else {
-	    IPOLATES(&interpol_type, ipopt,kgds,save->kgds_out, 
-		&ftn_npnts, &n_out, &km, &ibi, bitmap, data_in, &ftn_nout,
-		save->rlat,save->rlon, &ibo, bitmap_out, data_out, &iret);
-	}
-	if (iret != 0) {
-	    for (i = 0; i < 12; i++) {
-		fprintf(stderr," IPOLATES error: kgds[%d] input %d output %d\n", i+1,kgds[i],save->kgds_out[i]);
-	    }
-	    if (iret == 2) fatal_error("IPOLATES failed, unrecognized input grid or no grid point of output grid is in input grid","");
-	    if (iret == 3) fatal_error("IPOLATES failed, unrecognized output grid","");
-	    fatal_error_i("IPOLATES failed, error %d",iret);
-	   
-	}
-	n_out = (unsigned int) ftn_nout;
-
-        /* use bitmap to set UNDEFINED values */
-        if (ibo == 1) {         // has a bitmap
-	    if (is_v) {
-                for (i = 0; i < n_out; i++) {
-		    if (bitmap_out[i] == 0) data_out[i] = data_out[i+n_out] = UNDEFINED;
-		}
-	    }
-	    else {
-                for (i = 0; i < n_out; i++) {
-		    if (bitmap_out[i] == 0) data_out[i] = UNDEFINED;
-		}
-            }
-	} 
-
-	// now to write out the grib file
-
-	for (i = 0; i < 8; i++) new_sec[i] = sec[i];
-	new_sec[3] = save->sec3;
-
-	if (is_v != 0) {
-            GB2_ParmNum(new_sec) = GB2_ParmNum(new_sec) - 1;
-            grib_wrt(new_sec, data_out, n_out, nnx, nny, use_scale, dec_scale, bin_scale,
-                wanted_bits, max_bits, grib_type, &(save->out));
-            GB2_ParmNum(new_sec) = GB2_ParmNum(new_sec) + 1;
-            grib_wrt(new_sec, data_out+n_out, n_out, nnx, nny, use_scale, dec_scale, bin_scale,
-                wanted_bits, max_bits, grib_type, &(save->out));
-	}
-	else {
-            grib_wrt(new_sec, data_out, n_out, nnx, nny, use_scale, dec_scale, bin_scale,
-                wanted_bits, max_bits, grib_type, &(save->out));
-	}
-        if (flush_mode) fflush_file(&(save->out));
-        free(data_in);
-        free(bitmap);
-        free(bitmap_out);
-	free(data_out);
-	if (is_v != 0) {
-	    save->has_u = 0;
-            free(save->u_val);
-            free_sec(save->clone_sec);
-	}
-    }
-    return 0;
-}
-#endif
-
-#if USE_IPOLATES == 3
-
 /*
  * this is the double precision float and 4-byte integer version of grib2 version of ipolates
  * this version will not handle 2G+ grids (4 byte integers)
  * some optimizations relative to grib1 version and the single precision grib2 versions
  * of the wrappers
  *
- * spectral restored (removed from grib1 version because I didn't want to support it)
+ * spectral restored
  */
 
-#ifndef _IPOLATES_H
-#define _IPOLATES_h
-#include "ipolates.h"
-#endif
 
 extern int decode, latlon, file_append, flush_mode, header;
 extern int use_scale, dec_scale, bin_scale, wanted_bits, max_bits;
@@ -765,17 +167,17 @@ static int ipopt[20] = {-1,-1,0, 0,0,0, 0,0,0, 0};
 
 int f_new_grid_interpolation(ARG1) {
    
-#ifdef USE_SPECTRAL
+// #ifdef USE_SPECTRAL
    char type;
    int max_wave;
-#endif
+// #endif
 
    if (mode >= -1) {
        if (strcmp(arg1,"bilinear") == 0) { interpol_type = 0; ipopt[0] = -1; }
        else if (strcmp(arg1,"bicubic") == 0) { interpol_type = 1; ipopt[0] = 0; }
        else if (strcmp(arg1,"neighbor") == 0) { interpol_type = 2; ipopt[0] = 1; }
        else if (strcmp(arg1,"budget") == 0) { interpol_type = 3; ipopt[0] = -1; }
-#ifdef USE_SPECTRAL
+// #ifdef USE_SPECTRAL
        else if (sscanf(arg1,"spectral-%c%d", &type, &max_wave) == 2) {
             if (type == 't' || type == 'T') ipopt[0] = 0;
             else if (type == 'r' || type == 'R') ipopt[0] = 1;
@@ -784,7 +186,7 @@ int f_new_grid_interpolation(ARG1) {
 	    ipopt[1] = max_wave;
 	    interpol_type = 4;
        }
-#endif
+// #endif
       else if (strcmp(arg1,"neighbor-budget") == 0) { interpol_type = 6; ipopt[0] = -1; }
       else fatal_error("new_grid_interpolation: unknown type %s", arg1);
    }
@@ -1454,16 +856,16 @@ int f_new_grid(ARG4) {
         ftn_nout = (int) n_out;
 
         if (is_v) {
-            IPOLATEV(&tmp_interpol_type, ipopt, &gdtnum_in, &(gdt_in[0]), &gdt_in_size,
-                &(save->gdtnum_out), 
+            ipolatev_grib2_single_field(&tmp_interpol_type, ipopt, &gdtnum_in, &(gdt_in[0]), 
+		&gdt_in_size, &(save->gdtnum_out), 
 		&(save->gdt_out[0]), &(save->gdt_out_size),
                 &ftn_npnts, &ftn_nout, &km, &ibi, bitmap, data_in, data_in+ndata, &n_out,
                 save->rlat,save->rlon,save->crot,save->srot, &ibo, save->bitmap_out, save->data_out, 
                 save->data_out + n_out, &iret);
         }
         else {
-            IPOLATES(&tmp_interpol_type, ipopt, &gdtnum_in, &(gdt_in[0]), &gdt_in_size,
-                &(save->gdtnum_out), 
+            ipolates_grib2_single_field(&tmp_interpol_type, ipopt, &gdtnum_in, &(gdt_in[0]), 
+		&gdt_in_size, &(save->gdtnum_out), 
 		&(save->gdt_out[0]), &(save->gdt_out_size),
                 &ftn_npnts, &ftn_nout, &km, &ibi, bitmap, data_in, &n_out,
                 save->rlat,save->rlon, &ibo, save->bitmap_out, save->data_out, &iret);
@@ -1480,7 +882,7 @@ int f_new_grid(ARG4) {
             fatal_error_i("IPOLATES failed, error %d",iret);
         }
 
-        // save datda to data_wrt[]
+        // save data to data_wrt[]
 
 	if (ibo == 1) {		// has a bitmap
 #pragma omp parallel for private(i)
@@ -1591,7 +993,11 @@ int f_new_grid(ARG4) {
 
 #endif
 
-#if USE_IPOLATES == 0
+#ifndef USE_IPOLATES
+int f_new_grid_vectors(ARG1) {
+    fprintf(stderr,"IPOLATES package is not installed\n");
+    return 1;
+}
 int f_new_grid_interpolation(ARG1) {
     fprintf(stderr,"IPOLATES package is not installed\n");
     return 1;
diff --git a/wgrib2/init.c b/wgrib2/init.c
index 715f8f97..667bd5e6 100644
--- a/wgrib2/init.c
+++ b/wgrib2/init.c
@@ -261,7 +261,7 @@ void init_globals(void) {
     match_extra_fn_n = 0;
     strncpy(ndates_fmt," %s",4);
 
-#if USE_IPOLATES != 0
+#ifdef USE_IPOLATES
     wind_rotation = undefined;
     new_grid_format = grib;
 #endif
diff --git a/wgrib2/ncep_grids.c b/wgrib2/ncep_grids.c
index a72ba3e5..7e1cc2ae 100644
--- a/wgrib2/ncep_grids.c
+++ b/wgrib2/ncep_grids.c
@@ -8,7 +8,7 @@
 #include "fnlist.h"
 
 
-#if USE_IPOLATES > 0
+#ifdef USE_IPOLATES
 
 /*
  * ncep_grids:
diff --git a/wgrib2/wgrib2.h b/wgrib2/wgrib2.h
index 2d777c8b..4ab5495e 100644
--- a/wgrib2/wgrib2.h
+++ b/wgrib2/wgrib2.h
@@ -696,4 +696,16 @@ double get_unixtime(int year, int month, int day, int hour, int minute, int seco
 int JMA_Nb(unsigned char **sec);
 int JMA_Nr(unsigned char **sec);
 
+void ipolates_grib2_single_field(int *interpol, int *ipopt, int *gdt_in, int *gdttmpl_in, int *gdttmpl_size_in,
+  int *gdt_out, int *gdttmpl_out, int *gdttmpl_size_out, int *mi, int *mo, int *km,
+  int *ibi, unsigned char *bitmap, double *data_in, int *n_out, double *rlat, double *rlon,
+   int *ibo, unsigned char *bitmap_out, double *data_out, int *iret);
+
+void ipolatev_grib2_single_field(int *interpol, int *ipopt, int *gdt_in, int *gdttmpl_in, int *gdttmpl_size_in,
+  int *gdt_out, int *gdttmpl_out, int *gdttmpl_size_out, int *mi, int *mo, int *km,
+  int *ibi, unsigned char *bitmap, double *u_in, double *v_in, int *n_out, double *rlat, double *rlon,
+   double *crot, double *srot, int *ibo, unsigned char *bitmap_out,
+   double *u_out, double *v_out, int *iret);
+
+
 #endif /* _WGRIB2_H_ */
diff --git a/wgrib2/wgrib2_api.h b/wgrib2/wgrib2_api.h
index 637d4773..9cdbae76 100644
--- a/wgrib2/wgrib2_api.h
+++ b/wgrib2/wgrib2_api.h
@@ -12,7 +12,3 @@ int wgrib2_get_reg_data(float *data, size_t size, int reg);
 int wgrib2_set_reg(float *data, size_t size, int reg);
 
 int wgrib2_free_file(const char *filename);		// will delete files that are used/not used
-#ifndef _IPOLATES_H
-#define _IPOLATES_H
-#include "ipolates.h"
-#endif