cols <- cols_only(
Area = col_double(), Perim. = col_double(), Width = col_double(),
Height = col_double(), Major = col_double(), Minor = col_double(),
Circ. = col_double(), Feret = col_double(), MinFeret = col_double(),
AR = col_double(), Round = col_double(), Solidity = col_double(),
L_BlackBackground = col_double(), a_BlackBackground = col_double(),
b_BlackBackground = col_double(), L_GreenBackground = col_double(),
a_GreenBackground = col_double(), b_GreenBackground = col_double(),
Color_sd = col_double(), ColorNature = col_factor(),
Color_Name = col_factor(), Color_Category = col_factor(),
Group = col_factor(), RF_use = col_logical(),
File_Name = col_character(), Particle_Num = col_character()
)