{-# LANGUAGE OverloadedStrings #-}

import Text.LaTeX
import Text.LaTeX.Packages.Inputenc
import Data.Matrix

main :: IO ()
main = execLaTeXT tables >>= renderFile "tables.tex"

tables :: Monad m => LaTeXT m ()
tables = thePreamble >> document theBody

thePreamble :: Monad m => LaTeXT m ()
thePreamble = do
  documentclass [] article
  usepackage [utf8] inputenc
  author "Daniel Díaz"
  title "Examples of Tables"

theBody :: Monad m => LaTeXT m ()
theBody = do
  maketitle
  -- Table from a simple matrix
  center $ matrixTabular (fmap textbf ["x","y","z"]) $
    fromList 3 3 [ (1 :: Int)..]
  -- Table from a matrix calculated in-place
  center $ matrixTabular (fmap textbf ["Number","Square root"]) $
    matrix 9 2 $ \(i,j) -> if j == 1 then I i else R $ sqrt $ fromIntegral i

-- Creating custom instances of Texy to display elements
-- within a table.

data Number = R Double | I Int

instance Texy Number where
  texy (R x) = texy x
  texy (I i) = texy i