diff --git a/test/float_tests.c b/test/float_tests.c
new file mode 100644
index 0000000..1bff43c
--- /dev/null
+++ b/test/float_tests.c
@@ -0,0 +1,618 @@
+/*==============================================================================
+ float_tests.c -- tests for float and conversion to/from half-precision
+
+ Copyright 2018 Laurence Lundblade
+ 
+ Permission is hereby granted, free of charge, to any person obtaining
+ a copy of this software and associated documentation files (the
+ "Software"), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish,
+ distribute, sublicense, and/or sell copies of the Software, and to
+ permit persons to whom the Software is furnished to do so, subject to
+ the following conditions:
+ 
+ The above copyright notice and this permission notice shall be included
+ in all copies or substantial portions of the Software.
+ 
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ SOFTWARE.
+ 
+ (This is the MIT license)
+ ==============================================================================*/
+//  Created by Laurence Lundblade on 9/19/18.
+
+
+#include "float_tests.h"
+#include "qcbor.h"
+#include "half_to_double_from_rfc7049.h"
+#include <math.h> // For INFINITY and NAN and isnan()
+
+
+
+
+static uint8_t pExpectedEncodedFloat[] = {
+    0x98, 0x1e, 0xfa, 0x00, 0x00, 0x00, 0x00, 0xfa,
+    0x3f, 0x80, 0x00, 0x00, 0xfa, 0x3f, 0x8c, 0xcc,
+    0xcd, 0xfa, 0x3f, 0xc0, 0x00, 0x00, 0xfa, 0x47,
+    0x7f, 0xe0, 0x00, 0xfa, 0x47, 0xc3, 0x50, 0x00,
+    0xfa, 0x7f, 0x7f, 0xff, 0xff, 0xfa, 0x7f, 0x80,
+    0x00, 0x00, 0xfa, 0x33, 0x80, 0x00, 0x00, 0xfa,
+    0x38, 0x80, 0x00, 0x00, 0xfa, 0xc0, 0x80, 0x00,
+    0x00, 0xfa, 0xc0, 0x83, 0x33, 0x33, 0xfa, 0x7f,
+    0xc0, 0x00, 0x00, 0xfa, 0x7f, 0x80, 0x00, 0x00,
+    0xfa, 0xff, 0x80, 0x00, 0x00, 0xfb, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfb, 0x3f,
+    0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfb,
+    0x3f, 0xf1, 0x99, 0x99, 0x99, 0x99, 0x99, 0x9a,
+    0xfb, 0x3f, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0xfb, 0x40, 0xef, 0xfc, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xfb, 0x40, 0xf8, 0x6a, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0xfb, 0x47, 0xef, 0xff, 0xff,
+    0xe0, 0x00, 0x00, 0x00, 0xfb, 0x7e, 0x37, 0xe4,
+    0x3c, 0x88, 0x00, 0x75, 0x9c, 0xfb, 0x3e, 0x70,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfb, 0x3f,
+    0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfb,
+    0xc0, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0xfb, 0xc0, 0x10, 0x66, 0x66, 0x66, 0x66, 0x66,
+    0x66, 0xfb, 0x7f, 0xf8, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xfb, 0x7f, 0xf0, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0xfb, 0xff, 0xf0, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00};
+
+
+int FloatValuesTest1()
+{
+    QCBOREncodeContext ECtx;
+    int nReturn = 0;
+    
+    UsefulBuf_MakeStackUB(EncodedStorage, 1000);
+    
+    QCBOREncode_Init(&ECtx, EncodedStorage);
+    QCBOREncode_OpenArray(&ECtx);
+    
+    // These are all samples published
+    // in RFC 7049.
+    QCBOREncode_AddFloat(&ECtx, 0.0);
+    QCBOREncode_AddFloat(&ECtx, 1.0);
+    QCBOREncode_AddFloat(&ECtx, 1.1); // appx
+    QCBOREncode_AddFloat(&ECtx, 1.5);
+    QCBOREncode_AddFloat(&ECtx, 65504.0);
+    QCBOREncode_AddFloat(&ECtx, 100000.0);
+    QCBOREncode_AddFloat(&ECtx, 3.4028234663852886e+38);
+    QCBOREncode_AddFloat(&ECtx, 1.0e+300); // Infinity?
+    QCBOREncode_AddFloat(&ECtx, 5.960464477539063e-8);
+    QCBOREncode_AddFloat(&ECtx, 0.00006103515625);
+    QCBOREncode_AddFloat(&ECtx, -4.0);
+    QCBOREncode_AddFloat(&ECtx, -4.1); // appx
+    
+    QCBOREncode_AddFloat(&ECtx, NAN);
+    QCBOREncode_AddFloat(&ECtx, INFINITY);
+    QCBOREncode_AddFloat(&ECtx, -INFINITY);
+    
+    
+    QCBOREncode_AddDouble(&ECtx, 0.0);
+    QCBOREncode_AddDouble(&ECtx, 1.0);
+    QCBOREncode_AddDouble(&ECtx, 1.1); // appx
+    QCBOREncode_AddDouble(&ECtx, 1.5);
+    QCBOREncode_AddDouble(&ECtx, 65504.0);
+    QCBOREncode_AddDouble(&ECtx, 100000.0);
+    QCBOREncode_AddDouble(&ECtx, 3.4028234663852886e+38);
+    QCBOREncode_AddDouble(&ECtx, 1.0e+300); // Infinity?
+    QCBOREncode_AddDouble(&ECtx, 5.960464477539063e-8);
+    QCBOREncode_AddDouble(&ECtx, 0.00006103515625);
+    QCBOREncode_AddDouble(&ECtx, -4.0);
+    QCBOREncode_AddDouble(&ECtx, -4.1); // appx
+    
+    QCBOREncode_AddDouble(&ECtx, NAN);
+    QCBOREncode_AddDouble(&ECtx, INFINITY);
+    QCBOREncode_AddDouble(&ECtx, -INFINITY);
+    
+    QCBOREncode_CloseArray(&ECtx);
+    
+    UsefulBufC Encoded;
+    if(QCBOREncode_Finish2(&ECtx, &Encoded)) {
+        nReturn = -1;
+    }
+    
+    if(UsefulBuf_Compare(Encoded, UsefulBuf_FromByteArrayLiteral(pExpectedEncodedFloat))) {
+        nReturn = -2;
+    }
+    
+    //printencoded(pEncoded, nEncodedLen);
+    
+    return(nReturn);
+}
+
+
+
+
+static const uint8_t ExpectedHalf[] = {
+    0xB1,
+        0x64,
+            0x7A, 0x65, 0x72, 0x6F,
+        0xF9, 0x00, 0x00,   // 0.000
+        0x6A,
+            0x69, 0x6E, 0x66, 0x69, 0x6E, 0x69, 0x74, 0x69, 0x74, 0x79,
+        0xF9, 0x7C, 0x00,   // Infinity
+        0x73,
+            0x6E, 0x65, 0x67, 0x61, 0x74, 0x69, 0x76, 0x65, 0x20, 0x69, 0x6E, 0x66, 0x69, 0x6E, 0x69, 0x74, 0x69, 0x74, 0x79,
+        0xF9, 0xFC, 0x00,   // -Inifinity
+        0x63,
+            0x4E, 0x61, 0x4E,
+        0xF9, 0x7E, 0x00,   // NaN
+        0x63,
+            0x6F, 0x6E, 0x65,
+        0xF9, 0x3C, 0x00,   // 1.0
+        0x69,
+            0x6F, 0x6E, 0x65, 0x20, 0x74, 0x68, 0x69, 0x72, 0x64,
+        0xF9, 0x35, 0x55,   // 0.333251953125
+        0x76,
+            0x6C, 0x61, 0x72, 0x67, 0x65, 0x73, 0x74, 0x20, 0x68, 0x61, 0x6C, 0x66, 0x2D, 0x70, 0x72, 0x65, 0x63, 0x69, 0x73, 0x69, 0x6F, 0x6E,
+        0xF9, 0x7B, 0xFF,   // 65504.0
+        0x78, 0x18, 0x74, 0x6F, 0x6F, 0x2D, 0x6C, 0x61, 0x72, 0x67, 0x65, 0x20, 0x68, 0x61, 0x6C, 0x66, 0x2D, 0x70, 0x72, 0x65, 0x63, 0x69, 0x73, 0x69, 0x6F, 0x6E,
+        0xF9, 0x7C, 0x00,   // Infinity
+        0x72,
+            0x73, 0x6D, 0x61, 0x6C, 0x6C, 0x65, 0x73, 0x74, 0x20, 0x73, 0x75, 0x62, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C,
+        0xF9, 0x00, 0x01,   // 0.000000059604
+        0x6F,
+            0x73, 0x6D, 0x61, 0x6C, 0x6C, 0x65, 0x73, 0x74, 0x20, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C,
+        0xF9, 0x03, 0xFF,   // 0.0000609755516
+        0x71,
+            0x62, 0x69, 0x67, 0x67, 0x65, 0x73, 0x74, 0x20, 0x73, 0x75, 0x62, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C,
+        0xF9, 0x04, 0x00,   // 0.000061988
+        0x70,
+            0x73, 0x75, 0x62, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C, 0x20, 0x73, 0x69, 0x6E, 0x67, 0x6C, 0x65,
+        0xF9, 0x00, 0x00,
+        0x03,
+        0xF9, 0xC0, 0x00,    // -2
+        0x04,
+        0xF9, 0x7E, 0x00,    // qNaN
+        0x05,
+        0xF9, 0x7C, 0x01,    // sNaN
+        0x06,
+        0xF9, 0x7E, 0x0F,    // qNaN with payload 0x0f
+        0x07,
+        0xF9, 0x7C, 0x0F,    // sNaN with payload 0x0f
+    
+};
+
+
+
+int half_precision_encode_basic()
+{
+    UsefulBuf_MakeStackUB(EncodedHalfsMem, 250);
+
+    QCBOREncodeContext EC;
+    QCBOREncode_Init(&EC, EncodedHalfsMem);
+    // These are mostly from https://en.wikipedia.org/wiki/Half-precision_floating-point_format
+    QCBOREncode_OpenMap(&EC);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "zero", 0.00F);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "infinitity", INFINITY);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "negative infinitity", -INFINITY);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "NaN", NAN);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "one", 1.0F);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "one third", 0.333251953125F);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "largest half-precision",65504.0F);
+    // Float 65536.0F is 0x47800000 in hex. It has an exponent of 16, which is larger than 15, the largest half-precision exponent
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "too-large half-precision", 65536.0F);
+    // Should convert to smallest possible half precision which is encodded as 0x00 0x01 or 5.960464477539063e-8
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "smallest subnormal", 0.0000000596046448F);
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "smallest normal",    0.0000610351526F); // in hex single is 0x387fffff, exponent -15, significand 7fffff
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "biggest subnormal",  0.0000610351563F); // in hex single is 0x38800000, exponent -14, significand 0
+    QCBOREncode_AddFloatAsHalfToMap(&EC, "subnormal single", 4e-40F); 
+    QCBOREncode_AddFloatAsHalfToMapN(&EC, 3, -2.0F);
+    QCBOREncode_AddFloatAsHalfToMapN(&EC, 4, UsefulBufUtil_CopyUint32ToFloat(0x7fc00000L)); // qNaN
+    QCBOREncode_AddFloatAsHalfToMapN(&EC, 5, UsefulBufUtil_CopyUint32ToFloat(0x7f800001L)); // sNaN
+    QCBOREncode_AddFloatAsHalfToMapN(&EC, 6, UsefulBufUtil_CopyUint32ToFloat(0x7fc0f00fL)); // qNaN with payload
+    QCBOREncode_AddFloatAsHalfToMapN(&EC, 7, UsefulBufUtil_CopyUint32ToFloat(0x7f80f00fL)); // sNaN with payload
+    QCBOREncode_CloseMap(&EC);
+    
+    UsefulBufC EncodedHalfs;
+    int nReturn = QCBOREncode_Finish2(&EC, &EncodedHalfs);
+    if(nReturn) {
+        return -1;
+    }
+    
+    if(UsefulBuf_Compare(EncodedHalfs, UsefulBuf_FromByteArrayLiteral(ExpectedHalf))) {
+        return -3;
+    }
+    
+    return 0;
+}
+
+
+int half_precision_decode_basic()
+{
+    UsefulBufC HalfPrecision = UsefulBuf_FromByteArrayLiteral(ExpectedHalf);
+    
+    QCBORDecodeContext DC;
+    QCBORDecode_Init(&DC, HalfPrecision, 0);
+    
+    QCBORItem Item;
+
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_MAP) {
+        return -1;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 0.0F) {
+        return -2;
+    }
+    
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != INFINITY) {
+        return -3;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != -INFINITY) {
+        return -4;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item); // TODO, is this really converting right? It is carrying payload, but this confuses things.
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || !isnan(Item.val.fnum)) {
+        return -5;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 1.0F) {
+        return -6;
+    }
+    
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 0.333251953125F) {
+        return -7;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 65504.0F) {
+        return -8;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != INFINITY) {
+        return -9;
+    }
+    
+    QCBORDecode_GetNext(&DC, &Item); // TODO: check this
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 0.0000000596046448F) {
+        return -10;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item); // TODO: check this
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 0.0000609755516F) {
+        return -11;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item); // TODO check this
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 0.0000610351563F) {
+        return -12;
+    }
+    
+    QCBORDecode_GetNext(&DC, &Item); 
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != 0) {
+        return -13;
+    }
+    
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || Item.val.fnum != -2.0F) {
+        return -14;
+    }
+
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || UsefulBufUtil_CopyFloatToUint32(Item.val.fnum) != 0x7fc00000L) {
+        return -15;
+    }
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || UsefulBufUtil_CopyFloatToUint32(Item.val.fnum) != 0x7f800001) {
+        return -16;
+    }
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || UsefulBufUtil_CopyFloatToUint32(Item.val.fnum) != 0x7fc0000f) {
+        return -17;
+    }
+    QCBORDecode_GetNext(&DC, &Item);
+    if(Item.uDataType != QCBOR_TYPE_FLOAT || UsefulBufUtil_CopyFloatToUint32(Item.val.fnum) != 0x7f80000f) {
+        return -18;
+    }
+    
+    if(QCBORDecode_Finish(&DC)) {
+        return -19;
+    }
+    
+    return 0;
+}
+
+
+int half_precision_to_float_transitive_test()
+{
+    for(uint32_t uHalfP = 0; uHalfP < 0xffff; uHalfP += 1) {
+        // Contruct the CBOR for the half-precision float by hand
+        UsefulBuf_MakeStackUB(EncodedCBORMem, 3);
+        UsefulOutBuf UOB;
+        UsefulOutBuf_Init(&UOB, EncodedCBORMem);
+        
+        const uint8_t uHalfPrecInitialByte = HALF_PREC_FLOAT + (CBOR_MAJOR_TYPE_SIMPLE << 5); // 0xf9
+        UsefulOutBuf_AppendByte(&UOB, uHalfPrecInitialByte); // The initial byte for a half-precision float
+        UsefulOutBuf_AppendUint16(&UOB, (uint16_t)uHalfP);
+        
+        
+        // Now parse the hand-constructed CBOR. This will invoke the conversion to a float
+        QCBORDecodeContext DC;
+        QCBORDecode_Init(&DC, UsefulOutBuf_OutUBuf(&UOB), 0);
+        
+        QCBORItem Item;
+        QCBORDecode_GetNext(&DC, &Item);
+        if(Item.uDataType != QCBOR_TYPE_FLOAT) {
+            return -1;
+        }
+        
+        //printf("%04x  QCBOR:%15.15f  \n", uHalfP,Item.val.fnum);
+
+        
+        // Now generate CBOR with the half-precision value. This will invoke the conversion from float to half
+        UsefulBuf_MakeStackUB(OtherEncodedCBORMem, 5);
+        QCBOREncodeContext EC;
+        QCBOREncode_Init(&EC, OtherEncodedCBORMem);
+        QCBOREncode_AddFloatAsHalf(&EC, Item.val.fnum);
+        UsefulBufC EnCBOR;
+        QCBOREncode_Finish2(&EC, &EnCBOR); // todo check return code
+        
+        
+        // Finally parse the CBOR by hand to get at half-precision that was actually encoded.
+        UsefulInputBuf UIB;
+        UsefulInputBuf_Init(&UIB, EnCBOR);
+        if(UsefulInputBuf_GetByte(&UIB) != uHalfPrecInitialByte) {
+            return -2;
+        }
+        if(UsefulInputBuf_GetUint16(&UIB) != uHalfP) { // the moment of truth did we get back what we started with?
+            return -3;
+        }
+    }
+    
+    return 0;
+}
+
+
+int half_precision_to_float_vs_rfc_test()
+{
+    for(uint32_t uHalfP = 0; uHalfP < 0xffff; uHalfP += 60) {
+        unsigned char x[2];
+        x[1] = uHalfP & 0xff;
+        x[0] = uHalfP >> 8;
+        double d = decode_half(x);
+        
+        // Contruct the CBOR for the half-precision float by hand
+        UsefulBuf_MakeStackUB(__xx, 3);
+        UsefulOutBuf UOB;
+        UsefulOutBuf_Init(&UOB, __xx);
+        
+        const uint8_t uHalfPrecInitialByte = HALF_PREC_FLOAT + (CBOR_MAJOR_TYPE_SIMPLE << 5); // 0xf9
+        UsefulOutBuf_AppendByte(&UOB, uHalfPrecInitialByte); // The initial byte for a half-precision float
+        UsefulOutBuf_AppendUint16(&UOB, (uint16_t)uHalfP);
+
+        // Now parse the hand-constructed CBOR. This will invoke the conversion to a float
+        QCBORDecodeContext DC;
+        QCBORDecode_Init(&DC, UsefulOutBuf_OutUBuf(&UOB), 0);
+        
+        QCBORItem Item;
+        
+        QCBORDecode_GetNext(&DC, &Item);
+        if(Item.uDataType != QCBOR_TYPE_FLOAT) {
+            return -1;
+        }
+        
+        //printf("%04x  QCBOR:%15.15f  RFC: %15.15f (%8x)\n", uHalfP,Item.val.fnum, d , UsefulBufUtil_CopyFloatToUint32(d));
+        
+        if(isnan(d)) {
+            // The RFC code uses the native instructions which may or may not
+            // handle sNaN, qNaN and NaN payloads correctly. This test just
+            // makes sure it is a NaN and doesn't worry about the type of NaN
+            if(!isnan(Item.val.fnum)) {
+                return -3;
+            }
+        } else {
+            if(Item.val.fnum != d) {
+                return -2;
+            }
+        }
+    }
+    return 0;
+}
+
+
+/*
+ {"zero": 0.0, "negative zero": -0.0, "infinitity": Infinity, "negative infinitity": -Infinity, "NaN": NaN, "one": 1.0, "one third": 0.333251953125, "largest half-precision": 65504.0, "largest half-precision point one": 65504.1, "too-large half-precision": 65536.0, "smallest subnormal": 5.96046448e-8, "smallest normal": 0.00006103515261202119, "biggest subnormal": 0.00006103515625, "subnormal single": 4.00000646641519e-40, 3: -2.0, "large single exp": 2.5521177519070385e+38, "too-large single exp": 5.104235503814077e+38, "biggest single with prec": 16777216.0, "first single with prec loss": 16777217.0, 1: "fin"}
+ 
+ */
+static const uint8_t sExpectedSmallest[] = {
+    0xB4, 0x64, 0x7A, 0x65, 0x72, 0x6F, 0xF9, 0x00, 0x00, 0x6D, 0x6E, 0x65, 0x67, 0x61, 0x74, 0x69, 0x76, 0x65, 0x20, 0x7A, 0x65, 0x72, 0x6F, 0xF9, 0x80, 0x00, 0x6A, 0x69, 0x6E, 0x66, 0x69, 0x6E, 0x69, 0x74, 0x69, 0x74, 0x79, 0xF9, 0x7C, 0x00, 0x73, 0x6E, 0x65, 0x67, 0x61, 0x74, 0x69, 0x76, 0x65, 0x20, 0x69, 0x6E, 0x66, 0x69, 0x6E, 0x69, 0x74, 0x69, 0x74, 0x79, 0xF9, 0xFC, 0x00, 0x63, 0x4E, 0x61, 0x4E, 0xF9, 0x7E, 0x00, 0x63, 0x6F, 0x6E, 0x65, 0xF9, 0x3C, 0x00, 0x69, 0x6F, 0x6E, 0x65, 0x20, 0x74, 0x68, 0x69, 0x72, 0x64, 0xF9, 0x35, 0x55, 0x76, 0x6C, 0x61, 0x72, 0x67, 0x65, 0x73, 0x74, 0x20, 0x68, 0x61, 0x6C, 0x66, 0x2D, 0x70, 0x72, 0x65, 0x63, 0x69, 0x73, 0x69, 0x6F, 0x6E, 0xF9, 0x7B, 0xFF, 0x78, 0x20, 0x6C, 0x61, 0x72, 0x67, 0x65, 0x73, 0x74, 0x20, 0x68, 0x61, 0x6C, 0x66, 0x2D, 0x70, 0x72, 0x65, 0x63, 0x69, 0x73, 0x69, 0x6F, 0x6E, 0x20, 0x70, 0x6F, 0x69, 0x6E, 0x74, 0x20, 0x6F, 0x6E, 0x65, 0xFB, 0x40, 0xEF, 0xFC, 0x03, 0x33, 0x33, 0x33, 0x33, 0x78, 0x18, 0x74, 0x6F, 0x6F, 0x2D, 0x6C, 0x61, 0x72, 0x67, 0x65, 0x20, 0x68, 0x61, 0x6C, 0x66, 0x2D, 0x70, 0x72, 0x65, 0x63, 0x69, 0x73, 0x69, 0x6F, 0x6E, 0xFA, 0x47, 0x80, 0x00, 0x00, 0x72, 0x73, 0x6D, 0x61, 0x6C, 0x6C, 0x65, 0x73, 0x74, 0x20, 0x73, 0x75, 0x62, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C, 0xFB, 0x3E, 0x70, 0x00, 0x00, 0x00, 0x1C, 0x5F, 0x68, 0x6F, 0x73, 0x6D, 0x61, 0x6C, 0x6C, 0x65, 0x73, 0x74, 0x20, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C, 0xFA, 0x38, 0x7F, 0xFF, 0xFF, 0x71, 0x62, 0x69, 0x67, 0x67, 0x65, 0x73, 0x74, 0x20, 0x73, 0x75, 0x62, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C, 0xF9, 0x04, 0x00, 0x70, 0x73, 0x75, 0x62, 0x6E, 0x6F, 0x72, 0x6D, 0x61, 0x6C, 0x20, 0x73, 0x69, 0x6E, 0x67, 0x6C, 0x65, 0xFB, 0x37, 0xC1, 0x6C, 0x28, 0x00, 0x00, 0x00, 0x00, 0x03, 0xF9, 0xC0, 0x00, 0x70, 0x6C, 0x61, 0x72, 0x67, 0x65, 0x20, 0x73, 0x69, 0x6E, 0x67, 0x6C, 0x65, 0x20, 0x65, 0x78, 0x70, 0xFA, 0x7F, 0x40, 0x00, 0x00, 0x74, 0x74, 0x6F, 0x6F, 0x2D, 0x6C, 0x61, 0x72, 0x67, 0x65, 0x20, 0x73, 0x69, 0x6E, 0x67, 0x6C, 0x65, 0x20, 0x65, 0x78, 0x70, 0xFB, 0x47, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x78, 0x18, 0x62, 0x69, 0x67, 0x67, 0x65, 0x73, 0x74, 0x20, 0x73, 0x69, 0x6E, 0x67, 0x6C, 0x65, 0x20, 0x77, 0x69, 0x74, 0x68, 0x20, 0x70, 0x72, 0x65, 0x63, 0xFA, 0x4B, 0x80, 0x00, 0x00, 0x78, 0x1B, 0x66, 0x69, 0x72, 0x73, 0x74, 0x20, 0x73, 0x69, 0x6E, 0x67, 0x6C, 0x65, 0x20, 0x77, 0x69, 0x74, 0x68, 0x20, 0x70, 0x72, 0x65, 0x63, 0x20, 0x6C, 0x6F, 0x73, 0x73, 0xFB, 0x41, 0x70, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x01, 0x63, 0x66, 0x69, 0x6E
+};
+
+
+
+int double_as_smallest_encode_basic()
+{
+    UsefulBuf_MakeStackUB(EncodedHalfsMem, 420);
+    
+    QCBOREncodeContext EC;
+    QCBOREncode_Init(&EC, EncodedHalfsMem);
+    // These are mostly from https://en.wikipedia.org/wiki/Half-precision_floating-point_format
+    QCBOREncode_OpenMap(&EC);
+    // 64                                   # text(4)
+    //    7A65726F                          # "zero"
+    // F9 0000                              # primitive(0)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "zero", 0.00);
+
+    // 64                                   # text(4)
+    //    7A65726F                          # "negative zero"
+    // F9 8000                              # primitive(0)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "negative zero", -0.00);
+    
+    // 6A                                   # text(10)
+    //    696E66696E6974697479              # "infinitity"
+    // F9 7C00                              # primitive(31744)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "infinitity", INFINITY);
+    
+    // 73                                   # text(19)
+    //    6E6567617469766520696E66696E6974697479 # "negative infinitity"
+    // F9 FC00                              # primitive(64512)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "negative infinitity", -INFINITY);
+    
+    // 63                                   # text(3)
+    //    4E614E                            # "NaN"
+    // F9 7E00                              # primitive(32256)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "NaN", NAN);
+    
+    // TODO: test a few NaN variants
+    
+    // 63                                   # text(3)
+    //    6F6E65                            # "one"
+    // F9 3C00                              # primitive(15360)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "one", 1.0);
+    
+    // 69                                   # text(9)
+    //    6F6E65207468697264                # "one third"
+    // F9 3555                              # primitive(13653)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "one third", 0.333251953125);
+    
+    // 76                                   # text(22)
+    //    6C6172676573742068616C662D707265636973696F6E # "largest half-precision"
+    // F9 7BFF                              # primitive(31743)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "largest half-precision",65504.0);
+
+    // 76                                   # text(22)
+    //    6C6172676573742068616C662D707265636973696F6E # "largest half-precision"
+    // F9 7BFF                              # primitive(31743)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "largest half-precision point one",65504.1);
+    
+    // Float 65536.0F is 0x47800000 in hex. It has an exponent of 16, which is larger than 15, the largest half-precision exponent
+    // 78 18                                # text(24)
+    //    746F6F2D6C617267652068616C662D707265636973696F6E # "too-large half-precision"
+    // FA 47800000                          # primitive(31743)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "too-large half-precision", 65536.0);
+    
+    // The smallest possible half-precision subnormal, but digitis are lost converting
+    // to half, so this turns into a double
+    // 72                                   # text(18)
+    //    736D616C6C657374207375626E6F726D616C # "smallest subnormal"
+    // FB 3E700000001C5F68                  # primitive(4499096027744984936)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "smallest subnormal", 0.0000000596046448);
+    
+    // The smallest possible half-precision snormal, but digitis are lost converting
+    // to half, so this turns into a single TODO: confirm this is right
+    // 6F                                   # text(15)
+    //    736D616C6C657374206E6F726D616C    # "smallest normal"
+    // FA 387FFFFF                          # primitive(947912703)
+    // in hex single is 0x387fffff, exponent -15, significand 7fffff
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "smallest normal",    0.0000610351526F);
+    
+    // 71                                   # text(17)
+    //    62696767657374207375626E6F726D616C # "biggest subnormal"
+    // F9 0400                              # primitive(1024)
+    // in hex single is 0x38800000, exponent -14, significand 0
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "biggest subnormal",  0.0000610351563F);
+    
+    // 70                                   # text(16)
+    //    7375626E6F726D616C2073696E676C65  # "subnormal single"
+    // FB 37C16C2800000000                  # primitive(4017611261645684736)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "subnormal single", 4e-40F);
+    
+    // 03                                   # unsigned(3)
+    // F9 C000                              # primitive(49152)
+    QCBOREncode_AddDoubleAsSmallestToMapN(&EC, 3, -2.0);
+    
+    // 70                                   # text(16)
+    //    6C617267652073696E676C6520657870  # "large single exp"
+    // FA 7F400000                          # primitive(2134900736)
+    // (0x01LL << (DOUBLE_NUM_SIGNIFICAND_BITS-1)) | ((127LL + DOUBLE_EXPONENT_BIAS) << DOUBLE_EXPONENT_SHIFT);
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "large single exp", 2.5521177519070385E+38); // Exponent fits  single
+
+    // 74                                   # text(20)
+    //    746F6F2D6C617267652073696E676C6520657870 # "too-large single exp"
+    // FB 47F8000000000000                  # primitive(5185894970917126144)
+    // (0x01LL << (DOUBLE_NUM_SIGNIFICAND_BITS-1)) | ((128LL + DOUBLE_EXPONENT_BIAS) << DOUBLE_EXPONENT_SHIFT);
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "too-large single exp", 5.104235503814077E+38); // Exponent too large for single
+
+    // 66                                   # text(6)
+    //    646664666465                      # "dfdfde"
+    // FA 4B800000                          # primitive(1266679808)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "biggest single with prec",16777216); // Single with no precision loss
+    
+    // 78 18                                # text(24)
+    //    626967676573742073696E676C6520776974682070726563 # "biggest single with prec"
+    // FA 4B800000                          # primitive(1266679808)
+    QCBOREncode_AddDoubleAsSmallestToMap(&EC, "first single with prec loss",16777217); // Double becuase of precision loss
+    
+    // Just a convenient marker when cutting and pasting encoded CBOR
+    QCBOREncode_AddSZStringToMapN(&EC, 1, "fin");
+
+    QCBOREncode_CloseMap(&EC);
+    
+    UsefulBufC EncodedHalfs;
+    int nReturn = QCBOREncode_Finish2(&EC, &EncodedHalfs);
+    if(nReturn) {
+        return -1;
+    }
+    
+    if(UsefulBuf_Compare(EncodedHalfs, UsefulBuf_FromByteArrayLiteral(sExpectedSmallest))) {
+        return -3;
+    }
+    
+    return 0;
+};
+
+
+
+#ifdef NAN_EXPERIMENT
+/*
+ Code for checking what the double to float cast does with
+ NaNs.  Not run as part of tests. Keep it around to
+ be able to check various platforms and CPUs.
+ */
+
+#define DOUBLE_NUM_SIGNIFICAND_BITS (52)
+#define DOUBLE_NUM_EXPONENT_BITS    (11)
+#define DOUBLE_NUM_SIGN_BITS        (1)
+
+#define DOUBLE_SIGNIFICAND_SHIFT    (0)
+#define DOUBLE_EXPONENT_SHIFT       (DOUBLE_NUM_SIGNIFICAND_BITS)
+#define DOUBLE_SIGN_SHIFT           (DOUBLE_NUM_SIGNIFICAND_BITS + DOUBLE_NUM_EXPONENT_BITS)
+
+#define DOUBLE_SIGNIFICAND_MASK     (0xfffffffffffffULL) // The lower 52 bits
+#define DOUBLE_EXPONENT_MASK        (0x7ffULL << DOUBLE_EXPONENT_SHIFT) // 11 bits of exponent
+#define DOUBLE_SIGN_MASK            (0x01ULL << DOUBLE_SIGN_SHIFT) // 1 bit of sign
+#define DOUBLE_QUIET_NAN_BIT        (0x01ULL << (DOUBLE_NUM_SIGNIFICAND_BITS-1))
+
+
+static int NaNExperiments() {
+    double dqNaN = UsefulBufUtil_CopyUint64ToDouble(DOUBLE_EXPONENT_MASK | DOUBLE_QUIET_NAN_BIT);
+    double dsNaN = UsefulBufUtil_CopyUint64ToDouble(DOUBLE_EXPONENT_MASK | 0x01);
+    double dqNaNPayload = UsefulBufUtil_CopyUint64ToDouble(DOUBLE_EXPONENT_MASK | DOUBLE_QUIET_NAN_BIT | 0xf00f);
+    
+    float f1 = (float)dqNaN;
+    float f2 = (float)dsNaN;
+    float f3 = (float)dqNaNPayload;
+    
+    
+    uint32_t uqNaN = UsefulBufUtil_CopyFloatToUint32((float)dqNaN);
+    uint32_t usNaN = UsefulBufUtil_CopyFloatToUint32((float)dsNaN);
+    uint32_t uqNaNPayload = UsefulBufUtil_CopyFloatToUint32((float)dqNaNPayload);
+    
+    // Result of this on x86 is that every NaN is a qNaN. The intel
+    // CVTSD2SS instruction ignores the NaN payload and even converts
+    // a sNaN to a qNaN.
+    
+    return 0;
+}
+#endif
+
+
+