diff --git a/bench/Bench.hs b/bench/Bench.hs deleted file mode 100644 --- a/bench/Bench.hs +++ /dev/null @@ -1,7 +0,0 @@ -import BasicPrelude -import Criterion.Main - -main :: IO () -main = defaultMain - [ - ] diff --git a/gnss-converters.cabal b/gnss-converters.cabal --- a/gnss-converters.cabal +++ b/gnss-converters.cabal @@ -1,5 +1,5 @@ name: gnss-converters -version: 0.1.11 +version: 0.1.12 synopsis: GNSS Converters. description: Haskell bindings for GNSS converters. homepage: http://github.com/swift-nav/gnss-converters @@ -18,16 +18,22 @@ library hs-source-dirs: src exposed-modules: Data.RTCM3.SBP + , Data.RTCM3.SBP.Types , SwiftNav.SBP.RTCM3 ghc-options: -Wall build-depends: base >= 4.7 && < 5 , basic-prelude , conduit-extra + , exceptions , extra , lens + , monad-control + , mtl + , resourcet , rtcm , sbp , time + , transformers-base , unordered-containers default-language: Haskell2010 default-extensions: NoImplicitPrelude @@ -64,32 +70,20 @@ hs-source-dirs: test main-is: Test.hs other-modules: Test.Data.RTCM3.SBP - build-depends: base + build-depends: HUnit-approx + , base , basic-prelude , binary-conduit , bytestring , conduit , conduit-extra , gnss-converters - , HUnit-approx , lens , resourcet , sbp , tasty , tasty-hunit , unordered-containers - ghc-options: -threaded -rtsopts -with-rtsopts=-N -Wall - default-language: Haskell2010 - default-extensions: NoImplicitPrelude - -benchmark bench - type: exitcode-stdio-1.0 - hs-source-dirs: bench - main-is: Bench.hs - build-depends: base - , basic-prelude - , criterion - , gnss-converters ghc-options: -threaded -rtsopts -with-rtsopts=-N -Wall default-language: Haskell2010 default-extensions: NoImplicitPrelude diff --git a/main/RTCM32SBP.hs b/main/RTCM32SBP.hs --- a/main/RTCM32SBP.hs +++ b/main/RTCM32SBP.hs @@ -8,20 +8,22 @@ -- -- RTCM3 to SBP tool. -import BasicPrelude -import Control.Monad.Trans.Resource -import Data.Conduit -import Data.Conduit.Binary -import qualified Data.Conduit.List as CL -import Data.Conduit.Serialization.Binary -import Data.RTCM3.SBP -import System.IO +import BasicPrelude +import Control.Monad.Trans.Resource +import Data.Conduit +import Data.Conduit.Binary +import qualified Data.Conduit.List as CL +import Data.Conduit.Serialization.Binary +import Data.RTCM3.SBP +import Data.RTCM3.SBP.Types +import System.IO main :: IO () -main = runResourceT $ - sourceHandle stdin =$= - conduitDecode =$= - CL.mapMaybeM convert =$= - CL.concat =$= - conduitEncode $$ - sinkHandle stdout +main = do + s <- liftIO $ newStore + runResourceT $ runConvertT s $ + sourceHandle stdin =$= + conduitDecode =$= + CL.concatMapM convert =$= + conduitEncode $$ + sinkHandle stdout diff --git a/src/Data/RTCM3/SBP.hs b/src/Data/RTCM3/SBP.hs --- a/src/Data/RTCM3/SBP.hs +++ b/src/Data/RTCM3/SBP.hs @@ -12,15 +12,17 @@ module Data.RTCM3.SBP where -import BasicPrelude -import Control.Lens -import Data.Bits -import qualified Data.HashMap.Strict as H -import Data.List.Extra hiding (concat, map) -import Data.Time -import Data.Word -import Data.RTCM3 -import SwiftNav.SBP +import BasicPrelude +import Control.Lens +import Data.Bits +import qualified Data.HashMap.Strict as M +import Data.IORef +import Data.List.Extra hiding (concat, map) +import Data.RTCM3 +import Data.RTCM3.SBP.Types +import Data.Time +import Data.Word +import SwiftNav.SBP -------------------------------------------------------------------------------- @@ -104,17 +106,20 @@ -- | Map L2 codes to SBP GnssSignal codes -- -l2codeToSBPSignalCode :: H.HashMap Word8 Word8 -l2codeToSBPSignalCode = H.fromList [(0, l2CMSidCode), (1, l2PSidCode)] +l2codeToSBPSignalCode :: HashMap Word8 Word8 +l2codeToSBPSignalCode = M.fromList + [ (codeIndicator_L2C, l2CMSidCode) + , (codeIndicator_L2PD, l2PSidCode) + ] -- | Maximum number of packed observations to allow in a single SBP message. -- maxObsPerMessage :: Int -maxObsPerMessage = floor $ (maxPayloadSize - headerSize) / packedObsSize +maxObsPerMessage = (maxPayloadSize - headerSize) `div` packedObsSize where maxPayloadSize = 255 headerSize = 7 - packedObsSize = 16.0 + packedObsSize = 16 -------------------------------------------------------------------------------- @@ -124,12 +129,12 @@ fromEcefVal :: Int64 -> Double fromEcefVal x = fromIntegral x / 10000 -toGPSTime :: MonadIO m => GpsObservationHeader -> m ObsGPSTime +toGPSTime :: MonadStore e m => GpsObservationHeader -> m ObsGPSTime toGPSTime hdr = do - today <- utctDay <$> liftIO getCurrentTime + wn <- view storeWn >>= liftIO . readIORef return ObsGPSTime { _obsGPSTime_tow = hdr ^. gpsObservationHeader_tow - , _obsGPSTime_wn = fromIntegral $ div (diffDays today (fromGregorian 1980 1 6)) 7 + , _obsGPSTime_wn = wn } -- | Construct metric pseudorange (meters!) from L1 RTCM observation. @@ -169,7 +174,7 @@ lm = p + phaseRangeRes * fromIntegral (l1 ^. gpsL1Observation_carrierMinusCode) l = lm / (lightSpeedMS / l1frequency) li :: Int32 - li = floor (l) + li = floor l lf :: Word8 lf = truncate ((l - fromIntegral li) * q32Width) @@ -181,7 +186,7 @@ -> GpsL2Observation -> GpsL2ExtObservation -> CarrierPhase -toL_L2 l1 l1e l2 l2e = CarrierPhase +toL_L2 l1 l1e l2 _l2e = CarrierPhase { _carrierPhase_i = fromIntegral li , _carrierPhase_f = fromIntegral lf } where @@ -192,7 +197,7 @@ lm = p + phaseRangeRes * fromIntegral (l2 ^. gpsL2Observation_carrierMinusCode) l = lm / (lightSpeedMS / l2frequency) li :: Int32 - li = floor (l) + li = floor l lf :: Word8 lf = truncate ((l - fromIntegral li) * q32Width) @@ -210,7 +215,7 @@ -- | Construct sequenced SBP observation header -- -fromGpsObservationHeader :: MonadIO m +fromGpsObservationHeader :: MonadStore e m => Word8 -- ^ Total messages -> Word8 -- ^ Message in sequence -> GpsObservationHeader -- ^ RTCM observation header @@ -234,41 +239,52 @@ fromL1SatelliteObservation sat l1 l1e = -- Checks GPS L1 code indicator for RTCM message 1002. -- See DF016, pg. 3-17 of the RTCM3 spec. - if l1 ^. gpsL1Observation_code then - PackedObsContent - { _packedObsContent_P = toP_L1 l1 l1e - , _packedObsContent_L = toL_L1 l1 l1e - , _packedObsContent_cn0 = toCn0_L1 l1e - , _packedObsContent_lock = toLock_L1 l1 - , _packedObsContent_sid = GnssSignal - { _gnssSignal_sat = fromIntegral $ sat - 1 - , _gnssSignal_code = l1PSidCode - , _gnssSignal_reserved = 0 - } + PackedObsContent + { _packedObsContent_P = toP_L1 l1 l1e + , _packedObsContent_L = toL_L1 l1 l1e + , _packedObsContent_cn0 = toCn0_L1 l1e + , _packedObsContent_lock = toLock_L1 l1 + , _packedObsContent_sid = GnssSignal + { _gnssSignal_sat = fromIntegral $ sat - 1 + , _gnssSignal_code = if l1 ^. gpsL1Observation_code then l1PSidCode else l1CSidCode + , _gnssSignal_reserved = 0 } - else - PackedObsContent - { _packedObsContent_P = toP_L1 l1 l1e - , _packedObsContent_L = toL_L1 l1 l1e - , _packedObsContent_cn0 = toCn0_L1 l1e - , _packedObsContent_lock = toLock_L1 l1 - , _packedObsContent_sid = GnssSignal - { _gnssSignal_sat = fromIntegral $ sat - 1 - , _gnssSignal_code = l1CSidCode - , _gnssSignal_reserved = 0 - } + } + +-- | Construct an L2 SBP PackedObsContent an RTCM satellite vehicle observation +-- +fromL2SatelliteObservation :: Word8 -- ^ Satellite PRN + -> GpsL1Observation + -> GpsL1ExtObservation + -> GpsL2Observation + -> GpsL2ExtObservation + -> Maybe PackedObsContent +fromL2SatelliteObservation sat l1 l1e l2 l2e = do + -- Checks GPS L2 code indicator. + -- See DF016, pg. 3-17 of the RTCM3 spec. + code <- M.lookup (l2 ^. gpsL2Observation_code) l2codeToSBPSignalCode + return PackedObsContent + { _packedObsContent_P = toP_L2 l1 l1e l2 + , _packedObsContent_L = toL_L2 l1 l1e l2 l2e + , _packedObsContent_cn0 = toCn0_L2 l2e + , _packedObsContent_lock = toLock_L2 l2 + , _packedObsContent_sid = GnssSignal + { _gnssSignal_sat = fromIntegral $ sat - 1 + , _gnssSignal_code = code + , _gnssSignal_reserved = 0 } + } -- | Construct SBP GPS observation message (possibly chunked). -- -chunkToMsgObs :: MonadIO m - => Msg1004 -- ^ RTCM 1004 observation message - -> Word8 -- ^ Total messages - -> Word8 -- ^ Message in sequence +chunkToMsgObs :: MonadStore e m + => GpsObservationHeader -- ^ RTCM observation header + -> Word8 -- ^ Total messages + -> Word8 -- ^ Message in sequence -> [PackedObsContent] -> m MsgObs -chunkToMsgObs m totalMsgs n packed = do - header <- fromGpsObservationHeader totalMsgs n $ m ^. msg1004_header +chunkToMsgObs hdr totalMsgs n packed = do + header <- fromGpsObservationHeader totalMsgs n hdr return MsgObs { _msgObs_header = header , _msgObs_obs = packed @@ -287,72 +303,63 @@ -- | Construct an L1 SBP PackedObsContent from an RTCM Msg 1002. -- -fromObservation1002 :: Observation1002 -> Maybe PackedObsContent +fromObservation1002 :: Observation1002 -> [PackedObsContent] fromObservation1002 obs = -- Only lower set of PRN numbers (1-32) are supported - if sat > maxSats then Nothing else Just (fromL1SatelliteObservation sat l1 l1e) + if sat > maxSats then mempty else [fromL1SatelliteObservation sat l1 l1e] where sat = obs ^. observation1002_sat l1 = obs ^. observation1002_l1 l1e = obs ^. observation1002_l1e + -- | Convert an RTCM L1 1002 observation into an SBP MsgObs. -- -fromMsg1002 :: MonadIO m => Msg1002 -> m MsgObs +-- This chunking takes places because the number of observations in a given 1002 +-- may very well exceed the maximum SBP supported payload size of 255 bytes. +fromMsg1002 :: MonadStore e m => Msg1002 -> m [MsgObs] fromMsg1002 m = do - header <- fromGpsObservationHeader 1 0 (m ^. msg1002_header) - return MsgObs - { _msgObs_header = header - , _msgObs_obs = mapMaybe fromObservation1002 $ m ^. msg1002_observations - } + let hdr = m ^. msg1002_header + obs = concatMap fromObservation1002 $ m ^. msg1002_observations + chunks = zip [0..] $ chunksOf maxObsPerMessage obs + totalMsgs = fromIntegral $ length chunks + forM chunks $ uncurry $ chunkToMsgObs hdr totalMsgs -- | Construct an L1/L2 SBP PackedObsContent from an RTCM Msg 1004. -- -fromObservation1004 :: Observation1004 -> Maybe [PackedObsContent] +fromObservation1004 :: Observation1004 -> [PackedObsContent] fromObservation1004 obs = -- Only lower set of PRN numbers (1-32) are supported - if sat > maxSats then Nothing else mapM id [obs1, obs2] + if sat > maxSats then mempty else + maybe [obs1] (: [obs1]) obs2 where sat = obs ^. observation1004_sat l1 = obs ^. observation1004_l1 l1e = obs ^. observation1004_l1e -- Checks GPS L1 code indicator for RTCM message 1004 -- See DF016, pg. 3-17 of the RTCM3 spec. - obs1 = Just (fromL1SatelliteObservation sat l1 l1e) + obs1 = fromL1SatelliteObservation sat l1 l1e l2 = obs ^. observation1004_l2 l2e = obs ^. observation1004_l2e - code = l2 ^. gpsL2Observation_code -- Checks GPS L2 code indicator. -- See DF016, pg. 3-17 of the RTCM3 spec. - obs2 = if H.member code l2codeToSBPSignalCode then - Just PackedObsContent - { _packedObsContent_P = toP_L2 l1 l1e l2 - , _packedObsContent_L = toL_L2 l1 l1e l2 l2e - , _packedObsContent_cn0 = toCn0_L2 l2e - , _packedObsContent_lock = toLock_L2 l2 - , _packedObsContent_sid = GnssSignal - { _gnssSignal_sat = fromIntegral $ sat - 1 - , _gnssSignal_code = l2codeToSBPSignalCode H.! code - , _gnssSignal_reserved = 0 - } - } - else - Nothing + obs2 = fromL2SatelliteObservation sat l1 l1e l2 l2e -- | Convert an RTCM L1+L2 1004 observation into multiple SBP MsgObs. -- -- This chunking takes places because the number of observations in a given 1004 -- may very well exceed the maximum SBP supported payload size of 255 bytes. -fromMsg1004 :: MonadIO m => Msg1004 -> m [MsgObs] +fromMsg1004 :: MonadStore e m => Msg1004 -> m [MsgObs] fromMsg1004 m = do - let obs = concat $ mapMaybe fromObservation1004 $ m ^. msg1004_observations + let hdr = m ^. msg1004_header + obs = concatMap fromObservation1004 $ m ^. msg1004_observations chunks = zip [0..] $ chunksOf maxObsPerMessage obs totalMsgs = fromIntegral $ length chunks - mapM (\(n, packed) -> chunkToMsgObs m totalMsgs n packed) chunks + forM chunks $ uncurry $ chunkToMsgObs hdr totalMsgs -- | Convert an RTCM 1005 antenna reference position message into an SBP -- MsgBasePosEcef. -fromMsg1005 :: MonadIO m => Msg1005 -> m MsgBasePosEcef +fromMsg1005 :: MonadStore e m => Msg1005 -> m MsgBasePosEcef fromMsg1005 m = return MsgBasePosEcef { _msgBasePosEcef_x = fromEcefVal $ m ^. msg1005_reference ^. antennaReference_ecef_x @@ -362,7 +369,7 @@ -- | Convert an RTCM 1006 antenna reference position message into an SBP -- MsgBasePosEcef. -fromMsg1006 :: MonadIO m => Msg1006 -> m MsgBasePosEcef +fromMsg1006 :: MonadStore e m => Msg1006 -> m MsgBasePosEcef fromMsg1006 m = return MsgBasePosEcef { _msgBasePosEcef_x = fromEcefVal $ m ^. msg1006_reference ^. antennaReference_ecef_x @@ -372,22 +379,29 @@ -- | Convert an RTCM message into possibly multiple SBP messages. -- -convert :: MonadIO m => RTCM3Msg -> m (Maybe [SBPMsg]) +convert :: MonadStore e m => RTCM3Msg -> m [SBPMsg] convert = \case (RTCM3Msg1002 m _rtcm3) -> do let sender = m ^. msg1002_header ^. gpsObservationHeader_station m' <- fromMsg1002 m - return $ Just [SBPMsgObs m' $ toSBP m' $ toSender sender] + return $ flip fmap m' $ \x -> SBPMsgObs x $ toSBP x $ toSender sender (RTCM3Msg1004 m _rtcm3) -> do let sender = m ^. msg1004_header ^. gpsObservationHeader_station m' <- fromMsg1004 m - return $ Just (fmap (\x -> SBPMsgObs x $ toSBP x $ toSender sender) m') + return $ flip fmap m' $ \x -> SBPMsgObs x $ toSBP x $ toSender sender (RTCM3Msg1005 m _rtcm3) -> do let sender = m ^. msg1005_reference ^. antennaReference_station m' <- fromMsg1005 m - return $ Just [SBPMsgBasePosEcef m' $ toSBP m' $ toSender sender] + return [SBPMsgBasePosEcef m' $ toSBP m' $ toSender sender] (RTCM3Msg1006 m _rtcm3) -> do let sender = m ^. msg1006_reference ^. antennaReference_station m' <- fromMsg1006 m - return $ Just [SBPMsgBasePosEcef m' $ toSBP m' $ toSender sender] - _rtcm3Msg -> return Nothing + return [SBPMsgBasePosEcef m' $ toSBP m' $ toSender sender] + _rtcm3Msg -> return mempty + +newStore :: IO Store +newStore = do + day <- utctDay <$> getCurrentTime + let wn = fromIntegral $ div (diffDays day (fromGregorian 1980 1 6)) 7 + Store <$> newIORef wn + diff --git a/src/Data/RTCM3/SBP/Types.hs b/src/Data/RTCM3/SBP/Types.hs new file mode 100644 --- /dev/null +++ b/src/Data/RTCM3/SBP/Types.hs @@ -0,0 +1,74 @@ +{-# LANGUAGE ConstraintKinds #-} +{-# LANGUAGE FlexibleInstances #-} +{-# LANGUAGE GeneralizedNewtypeDeriving #-} +{-# LANGUAGE MultiParamTypeClasses #-} +{-# LANGUAGE TemplateHaskell #-} +{-# LANGUAGE TypeFamilies #-} +{-# LANGUAGE UndecidableInstances #-} + +-- | +-- Module: Data.RTCM3.SBP.Types +-- Copyright: Copyright (C) 2015 Swift Navigation, Inc. +-- License: LGPL-3 +-- Maintainer: Mark Fine +-- Stability: experimental +-- Portability: portable +-- +-- Types for RTCMv3 to SBP Conversions. + +module Data.RTCM3.SBP.Types where + +import BasicPrelude +import Control.Lens +import Control.Monad.Base +import Control.Monad.Catch +import Control.Monad.Reader +import Control.Monad.Trans.Control +import Control.Monad.Trans.Resource +import Data.IORef +import Data.Word + +newtype ConvertT e m a = ConvertT { unConvertT :: ReaderT e m a } + deriving + ( Functor + , Applicative + , Monad + , MonadIO + , MonadTrans + ) + +instance MonadThrow m => MonadThrow (ConvertT r m) where + throwM = lift . throwM + +instance MonadResource m => MonadResource (ConvertT r m) where + liftResourceT = lift . liftResourceT + +instance Monad m => MonadReader e (ConvertT e m) where + ask = ConvertT ask + local f = ConvertT . local f . unConvertT + reader = ConvertT . reader + +instance MonadTransControl (ConvertT r) where + type StT (ConvertT r) a = StT (ReaderT r) a + + liftWith = defaultLiftWith ConvertT unConvertT + restoreT = defaultRestoreT ConvertT + +instance MonadBase b m => MonadBase b (ConvertT r m) where + liftBase = liftBaseDefault + +data Store = Store + { _storeWn :: IORef Word16 + } deriving ( Eq ) + +$(makeClassy ''Store) + +runConvertT :: HasStore e => e -> ConvertT e m a -> m a +runConvertT e (ConvertT m) = runReaderT m e + +type MonadStore e m = + ( MonadIO m + , MonadReader e m + , MonadThrow m + , HasStore e + ) diff --git a/src/SwiftNav/SBP/RTCM3.hs b/src/SwiftNav/SBP/RTCM3.hs --- a/src/SwiftNav/SBP/RTCM3.hs +++ b/src/SwiftNav/SBP/RTCM3.hs @@ -31,10 +31,10 @@ convert :: SBPMsg -> Maybe RTCM3Msg convert = \case - (SBPMsgObs msg _sbp) -> Just $ - RTCM3Msg1002 msg' $ toRTCM3 msg' where - msg' = fromMsgObs msg - (SBPMsgBasePosEcef msg _sbp) -> Just $ - RTCM3Msg1005 msg' $ toRTCM3 msg' where - msg' = fromMsgBasePosEcef msg + (SBPMsgObs m _sbp) -> Just $ + RTCM3Msg1002 m' $ toRTCM3 m' where + m' = fromMsgObs m + (SBPMsgBasePosEcef m _sbp) -> Just $ + RTCM3Msg1005 m' $ toRTCM3 m' where + m' = fromMsgBasePosEcef m _sbpMsg -> Nothing diff --git a/test/Test.hs b/test/Test.hs --- a/test/Test.hs +++ b/test/Test.hs @@ -1,6 +1,3 @@ -{-# LANGUAGE NoImplicitPrelude #-} -{-# LANGUAGE OverloadedStrings #-} - -- | -- Module: Test -- Copyright: (c) 2016 Swift Navigation Inc. diff --git a/test/Test/Data/RTCM3/SBP.hs b/test/Test/Data/RTCM3/SBP.hs --- a/test/Test/Data/RTCM3/SBP.hs +++ b/test/Test/Data/RTCM3/SBP.hs @@ -1,8 +1,4 @@ -{-# LANGUAGE FlexibleContexts #-} -{-# LANGUAGE LambdaCase #-} -{-# LANGUAGE NoImplicitPrelude #-} -{-# LANGUAGE OverloadedStrings #-} -{-# LANGUAGE RecordWildCards #-} +{-# LANGUAGE FlexibleContexts #-} -- | -- Module: Test.Data.RTCM3.SBP @@ -16,30 +12,30 @@ ( tests ) where -import BasicPrelude -import Control.Lens -import Control.Monad.Trans.Resource -import Data.Conduit -import Data.Conduit.Binary -import Data.Conduit.Serialization.Binary -import Data.HashMap.Strict -import Data.RTCM3.SBP -import qualified Data.Conduit.List as CL -import Data.Word -import SwiftNav.SBP -import Test.HUnit.Approx -import Test.Tasty -import Test.Tasty.HUnit +import BasicPrelude +import Control.Lens +import Control.Monad.Trans.Resource +import Data.Conduit +import Data.Conduit.Binary +import qualified Data.Conduit.List as CL +import Data.Conduit.Serialization.Binary +import Data.HashMap.Strict +import Data.IORef +import Data.RTCM3.SBP +import Data.RTCM3.SBP.Types +import Data.Word +import SwiftNav.SBP +import Test.HUnit.Approx +import Test.Tasty +import Test.Tasty.HUnit -decodeRTCMFile :: (MonadIO m, MonadBaseControl IO m, MonadThrow m) - => FilePath - -> m [SBPMsg] -decodeRTCMFile filename = - runResourceT . runConduit $ - sourceFile filename =$= - conduitDecode =$= - CL.mapMaybeM convert =$= - CL.concat $$ +decodeRTCMFile :: FilePath -> IO [SBPMsg] +decodeRTCMFile filename = do + wn <- liftIO $ newIORef 1906 + runResourceT $ runConvertT (Store wn) $ runConduit $ + sourceFile filename =$= + conduitDecode =$= + CL.concatMapM convert $$ CL.consume basePosition :: MsgBasePosEcef -> (Double, Double, Double) @@ -160,39 +156,39 @@ assertExpectedBase (msgs !! 5) expectedBasePos -- Message 1 assertObsHeader (msgs !! 1) ObservationHeader { - _observationHeader_t = ObsGPSTime 86354000 1905 + _observationHeader_t = ObsGPSTime 86354000 1906 , _observationHeader_n_obs = 32 } assertMsgObsLength (msgs !! 1) 15 assertMsgObs (msgs !! 1) -- Message 2 assertObsHeader (msgs !! 2) ObservationHeader { - _observationHeader_t = ObsGPSTime 86354000 1905 + _observationHeader_t = ObsGPSTime 86354000 1906 , _observationHeader_n_obs = 33 } assertMsgObs (msgs !! 2) assertMsgObsLength (msgs !! 2) 1 -- Message 3 assertObsHeader (msgs !! 3) ObservationHeader { - _observationHeader_t = ObsGPSTime 86355000 1905 + _observationHeader_t = ObsGPSTime 86355000 1906 , _observationHeader_n_obs = 32 } assertMsgObsLength (msgs !! 3) 15 -- Message 4 assertObsHeader (msgs !! 4) ObservationHeader { - _observationHeader_t = ObsGPSTime 86355000 1905 + _observationHeader_t = ObsGPSTime 86355000 1906 , _observationHeader_n_obs = 33 } assertMsgObsLength (msgs !! 4) 1 -- Message 6 assertObsHeader (msgs !! 6) ObservationHeader { - _observationHeader_t = ObsGPSTime 86356000 1905 + _observationHeader_t = ObsGPSTime 86356000 1906 , _observationHeader_n_obs = 32 } assertMsgObsLength (msgs !! 6) 15 -- Message 7 assertObsHeader (msgs !! 7) ObservationHeader { - _observationHeader_t = ObsGPSTime 86356000 1905 + _observationHeader_t = ObsGPSTime 86356000 1906 , _observationHeader_n_obs = 33 } assertMsgObsLength (msgs !! 7) 1