Float utility

This commit is contained in:
Dan Paulat 2022-04-08 01:34:36 -05:00
parent 711993362c
commit 3fc6837f2a
5 changed files with 132 additions and 3 deletions

View file

@ -0,0 +1,50 @@
#include <scwx/util/float.hpp>
#include <gtest/gtest.h>
namespace scwx
{
namespace util
{
TEST(FloatTest, Decode32Positive1)
{
uint16_t msw = 0x3f80;
uint16_t lsw = 0x0000;
float x = DecodeFloat32(msw, lsw);
EXPECT_FLOAT_EQ(x, 1.0f);
}
TEST(FloatTest, Decode32Negative1)
{
uint16_t msw = 0xbf80;
uint16_t lsw = 0x0000;
float x = DecodeFloat32(msw, lsw);
EXPECT_FLOAT_EQ(x, -1.0f);
}
TEST(FloatTest, Decode32Positive12345678)
{
uint16_t msw = 0x4b3c;
uint16_t lsw = 0x614e;
float x = DecodeFloat32(msw, lsw);
EXPECT_FLOAT_EQ(x, 12345678.0f);
}
TEST(FloatTest, Decode16h0x5bb4)
{
uint16_t hex = 0x5bb4;
float x = DecodeFloat16(hex);
EXPECT_FLOAT_EQ(x, 123.25f);
}
} // namespace util
} // namespace scwx

View file

@ -15,7 +15,8 @@ set(SRC_AWIPS_TESTS source/scwx/awips/coded_location.test.cpp
set(SRC_COMMON_TESTS source/scwx/common/color_table.test.cpp)
set(SRC_QT_CONFIG_TESTS source/scwx/qt/config/radar_site.test.cpp)
set(SRC_QT_MANAGER_TESTS source/scwx/qt/manager/settings_manager.test.cpp)
set(SRC_UTIL_TESTS source/scwx/util/rangebuf.test.cpp
set(SRC_UTIL_TESTS source/scwx/util/float.test.cpp
source/scwx/util/rangebuf.test.cpp
source/scwx/util/streams.test.cpp
source/scwx/util/vectorbuf.test.cpp)
set(SRC_WSR88D_TESTS source/scwx/wsr88d/ar2v_file.test.cpp

View file

@ -0,0 +1,14 @@
#pragma once
#include <cstdint>
namespace scwx
{
namespace util
{
float DecodeFloat16(uint16_t hex);
float DecodeFloat32(uint16_t msw, uint16_t lsw);
} // namespace util
} // namespace scwx

View file

@ -0,0 +1,62 @@
#include <scwx/util/float.hpp>
#include <cmath>
#ifdef WIN32
# include <WinSock2.h>
#else
# include <arpa/inet.h>
#endif
namespace scwx
{
namespace util
{
float DecodeFloat16(uint16_t hex)
{
static constexpr uint16_t S_MASK = 0x8000;
static constexpr uint16_t S_LSB = 0;
static constexpr uint16_t S_SHIFT = 15 - S_LSB;
static constexpr uint16_t E_MASK = 0x7a00;
static constexpr uint16_t E_LSB = 5;
static constexpr uint16_t E_SHIFT = 15 - E_LSB;
static constexpr uint16_t F_MASK = 0x03ff;
static constexpr uint16_t F_LSB = 15;
static constexpr uint16_t F_SHIFT = 15 - F_LSB;
uint16_t sHex = (hex & S_MASK) >> S_SHIFT;
uint16_t eHex = (hex & E_MASK) >> E_SHIFT;
uint16_t fHex = (hex & F_MASK) >> F_SHIFT;
float value;
float s = std::pow(-1.0f, static_cast<float>(sHex));
float e;
float f;
if (eHex == 0)
{
e = 2.0f;
f = (fHex / std::pow(2.0f, 10.0f));
}
else
{
e = std::pow(2.0f, eHex - 16.0f);
f = (1 + fHex / std::pow(2.0f, 10.0f));
}
value = s * e * f;
return value;
}
float DecodeFloat32(uint16_t msw, uint16_t lsw)
{
uint32_t value = msw << 16 | lsw;
return reinterpret_cast<float&>(value);
}
} // namespace util
} // namespace scwx

View file

@ -32,13 +32,15 @@ set(SRC_COMMON source/scwx/common/color_table.cpp
source/scwx/common/products.cpp
source/scwx/common/sites.cpp
source/scwx/common/vcp.cpp)
set(HDR_UTIL include/scwx/util/iterator.hpp
set(HDR_UTIL include/scwx/util/float.hpp
include/scwx/util/iterator.hpp
include/scwx/util/rangebuf.hpp
include/scwx/util/streams.hpp
include/scwx/util/threads.hpp
include/scwx/util/time.hpp
include/scwx/util/vectorbuf.hpp)
set(SRC_UTIL source/scwx/util/rangebuf.cpp
set(SRC_UTIL source/scwx/util/float.cpp
source/scwx/util/rangebuf.cpp
source/scwx/util/streams.cpp
source/scwx/util/time.cpp
source/scwx/util/vectorbuf.cpp)