Formatted printing

see : https://www.gnu.org/software/gawk/manual/html_node/Printf.html#Printf

{ print $1 $2 } # will concatenate the referenced fields into a single string.

{ print $1, $2 } # will display the listed field using the OFS, output field separator.

awk provides a version of the c-type printf for a more controlled printing facility.

printf ( format , argument[s] );

format - quoted string with % positional references to argument[s] list.
argument[s] list - comma delimit list to variables or constants.
{ printf ( "Cost : %f\n", $2 ); } - prints 2nd record field as a float.
Cost : 33.73

Each positional format reference must be matched by a constant or variable in the argument[s] list.
Format is specified by a % followed by a character representing the data type a particular positional argument should be treated as.

%c - ASCII character
%d - decimal integer
%i - decimal integer (POSIX)
%e - float, scientific form d.precisione+/-dd - 7.235e23
%E - float, scientific form d.precisionE+/-dd - 7.235E23
%f - float. d.precision - 732.257
%g or G - picks shortest representation between e and f or E and f
%o - unsigned octal.
%s - string.
%x - hexadecimal, 0-9a-f.
%X - hexadecimal, 0-9A-F.
%% - literal %

Several of these will take numeric modifiers to set default column sizes.

{ printf ( "%6.3f\n", $2 ); }

Given the data file :

martinets 1
Lorrie's 2.2
pooched 3.33
excoriation 44.44
pries 55.555
caravan 66.6666
handballs 77.77777
slap 88.888888
specially 12
woeful 1212
added 12.1212
rocky a1a1
door a1a2

and the awk command sequence :

awk '{ printf ( "%6.3f\n", $2 ); }' data

Output would be :

1.000 2.200 3.330 44.440 55.555 66.667 77.778 88.889 12.000 1212.000 12.121 0.000 0.000

The . counts as one of the characters.

printf attempts to align the decimal point. If the integer portion is larger than the format specified, alignment is skewed, but all digits displayed.

The fractional portion will be rounded to fit 3 characters and all digits displayed.

The following also prints the topic field, $1

awk '{ printf ( "%10s %6.3f\n", $1, $2 ); }' data

martinets 1.000 Lorrie's 2.200 booched 3.330 excoriation 44.440 pries 55.555 caravan 66.667 handballs 77.778 slap 88.889 specially 12.000 woeful 1212.000 added 12.121 Added 12.121 rocky 0.000 boor 0.000

There are several 'issues' with this, text is right justified, several of the floats are still not aligned.

The -, minus, can be used to left justify the text.

And the default size for both data fields can be increased.

awk '{ printf ( "%-14s %8.3f\n", $1, $2 ); }' data

Output would be :

martinets 1.000 Lorrie's 2.200 pooched 3.330 excoriation 44.440 pries 55.555 caravan 66.667 handballs 77.778 slap 88.889 specially 12.000 woeful 1212.000 added 12.121 rocky 0.000 door 0.000

Some additional observations:

The minus is more useful when working with strings.
Using float or other numeric formats on a non-numeric value outputs a zero.
The \n, new-line, specifier is required if you want to do a line feed.
Using printf without line feeds will allow you to build an output line from multiple printfs.
Various escape characters available:
- \t - tab
- \n - newline
- \f - form feed (next page)
- \r - return to start of same line.
- \v - vertical tab, move down a line but not back to the start of the line. \v\r essentially equals \n
sprintf - variation that allows you to assign output to variable.