Optionally, colex will format output columns as integers, numbers with decimal points, or as numbers in exponential (scientific) notation, instead of the default of printing the columns as alphabetic fields. A format specification precedes the column range and is indicated by a single letter: a (alphabetic), e (exponential), i (integer), and n (numeric). Each format can be preceded by an optional width and/or a precision. The width tells how wide the field should be. The precision tells how many digits after the decimal point should be printed for real numbers, or the maximum width for alphabetic fields. The general form is:

[[width][.precision]format][column range]

-c

Character column mode, to allow extracting fixed format data. By default, colex extracts white-space-separated columns, but with this option, input lines are treated as a series of characters. No type checking is supported with this option, and extracted columns can not be quoted. This option should usually be used with the option to inhibit tabs between columns.

-f

Force filling of missing columns with the string NA.

-F format

By default, columns without type specifiers are printed as alphabetic strings. This option changes the default for all columns for which the format is not explicitly specified.

-i

Ignore missing columns. Otherwise, a missing column, not filled by the -f option, is an error.

-q

Place quotes around the printed strings.

-t

By default, there is a tab printed after every column. This option turns off the tab printing.

-v

Validate data types in numerical columns. If a numerical output format is requested, validation will print warnings when a non- integer or non-number is being printed as a number (usually as 0). By default, no checking is done.

-L

Display limits

-O

Display options and values

-V

Display version number and date

colex 1 2 3 4       # columns 1 through 4
colex 1-4           # an abbreviation of the above
colex 4-1           # columns 4-1 in reverse order
colex -i 100-1      # reverse the columns ignoring missing columns
colex 10.2n1-5      # columns 1-5, 10-wide, with 2 digits after decimal place
colex -F 10.2n 5-2  # columns 5-2 in 10.2n format
colex 4i1 5.2n2-3 10a4# column 1 as a 4-wide integer,
                      # columns 2-3 as 5-wide numbers with 2 decimal digits,
                      # and column 4 as a 10-wide alphabetic string
colex -tc 12-14     # extract characters 12-14 (3 characters wide)