formatC(x, format = NULL, digits = y, flag = "")
#format = g #Fixed format unless sci save space
# = f #Fixed format
# = e #Sci format
#y = no. of significant figure (sci)
# = no. of digit after decimal point (fixed)
# flag = "+" #Force display sign
# = "-" #Left align numbers
# = "0" #Pad numbers with leading zero