add --precision option

app/Main.hs

@@ -6,11 +6,20 @@ import GEval.OptionsParser
 import System.Environment
 import Options.Applicative
 
+import Text.Printf
+
 main :: IO ()
 main = do
   args <- getArgs
-  result <- runGEval args
+  result <- runGEvalGetOptions args
   case result of
     Left parseResult -> handleParseResult parseResult >> return ()
-    Right (Just result) -> print $ result
+    Right (opts, Just result) -> showTheResult opts result
-    Right Nothing -> return ()
+    Right (_, Nothing) -> return ()
+
+showTheResult :: GEvalOptions -> MetricValue -> IO ()
+showTheResult opts val = putStrLn $ formatTheResult (geoPrecision opts) val
+
+formatTheResult :: Maybe Int -> MetricValue -> String
+formatTheResult Nothing  = show
+formatTheResult (Just prec) = printf "%0.*f" prec

geval.cabal

@@ -1,5 +1,5 @@
 name:                geval
-version:             0.1.0.0
+version:             0.1.1.0
 synopsis:            Machine learning evaluation tools
 description:         Please see README.md
 homepage:            http://github.com/name/project

src/GEval/Core.hs

@@ -66,6 +66,7 @@ getExpectedDirectory spec = fromMaybe outDirectory $ gesExpectedDirectory spec
 
 data GEvalOptions = GEvalOptions
                     { geoInit :: Bool,
+                      geoPrecision :: Maybe Int,
                       geoSpec :: GEvalSpecification }
 
 

src/GEval/OptionsParser.hs

@@ -2,7 +2,8 @@
 
 module GEval.OptionsParser
        (fullOptionsParser,
-        runGEval) where
+        runGEval,
+        runGEvalGetOptions) where
 
 import Options.Applicative
 import qualified System.Directory as D
@@ -25,8 +26,15 @@ optionsParser = GEvalOptions
    <$> switch
       ( long "init"
          <> help "Init a sample Gonito challenge rather than run an evaluation" )
+   <*> optional precisionArgParser
    <*> specParser
 
+precisionArgParser :: Parser Int
+precisionArgParser = option auto
+    ( long "precision"
+      <> metavar "PRECISION"
+      <> help "Precision with which the evaluation results should be shown" )
+
 specParser :: Parser GEvalSpecification
 specParser = GEvalSpecification
   <$> strOption
@@ -68,18 +76,28 @@ metricReader = option auto
                  <> help "Metric to be used - RMSE, MSE or BLEU" )
 
 runGEval :: [String] -> IO (Either (ParserResult GEvalOptions) (Maybe MetricValue))
-runGEval = runGEval' True
+runGEval args = do
+  ret <- runGEvalGetOptions args
+  case ret of
+    Left e -> return $ Left e
+    Right (_, mmv) -> return $ Right mmv
 
-runGEval' :: Bool -> [String] -> IO (Either (ParserResult GEvalOptions) (Maybe MetricValue))
+runGEvalGetOptions :: [String] -> IO (Either (ParserResult GEvalOptions) (GEvalOptions, Maybe MetricValue))
+runGEvalGetOptions = runGEval' True
+
+-- the first argument: whether to try to read from the config file
+runGEval' :: Bool -> [String] -> IO (Either (ParserResult GEvalOptions) (GEvalOptions, Maybe MetricValue))
 runGEval' readOptsFromConfigFile args =
   case parserResult of
     Success opts -> if readOptsFromConfigFile then
                       attemptToReadOptsFromConfigFile args opts else
-                      Right <$> runGEval'' opts
+                        do
+                          mmv <- runGEval'' opts
+                          return $ Right $ (opts, mmv)
     otherwise -> return $ Left parserResult
   where parserResult = execParserPure (prefs idm) fullOptionsParser args
 
-attemptToReadOptsFromConfigFile :: [String] -> GEvalOptions -> IO (Either (ParserResult GEvalOptions) (Maybe MetricValue))
+attemptToReadOptsFromConfigFile :: [String] -> GEvalOptions -> IO (Either (ParserResult GEvalOptions) (GEvalOptions, Maybe MetricValue))
 attemptToReadOptsFromConfigFile args opts = do
   configExists <- D.doesFileExist configFilePath
   if configExists then do