There are several issues with processing such small numbers (2e-318) in awk.

• First, the input needs to be converted to a number before using it. That is usually done by adding 0. So, you need something like:

   val=0+$1 

• Second, Normal double precision floats (53 bit mantissa and 11 bit exponent) The 11 bit width of the exponent allows the representation of numbers between 10e-308 and 10e308, so, normal floats will not be able to represent such numbers.

   $ echo '1e-307 1e-308' | awk '{print $1,$1+0,$2,$2+0}' 1e-307 1e-307 1e-308 0 

Default GNU awk will not accept (normal) values below 1e-308.

• Third, The default conversion format for awk (both CNVFMT and OFMT) are set to "%.6g". Numbers with more than 6 significant figures will be truncated.

• Fourth, It is better to set the first value of max to the first input. Setting max to 0 will fail if input has a negative maximum.

If you are using GNU awk and it has been compiled with arbitrary precision you can use:

$ printf '%s\n' 2e-318 2e-317 2e-307 2e-308 2e-319 | awk -M -v PREC=100 'BEGIN{CONVFMT="%e"}; {val=0+$1}; NR==1{max=val}; {print($1,val,max)}; val>max{max=val} END{print max}' 2e-318 2e-318 2e-318 2e-317 2e-317 2e-318 2e-307 2e-307 2e-317 2e-308 2e-308 2e-307 2e-319 2e-319 2e-307 2e-307 

Or simplified to your use case:

awk -M -v PREC=100 ' BEGIN{CONVFMT="%e"}; # allow more than 6 figures {val=0+$1}; # convert input to a (float) number. NR==1{max=val}; # On the first line, set the max value. val>max{max=val} # On every entry keep track of the max. END{print max} # At the end, print the max. ' file # file with input (one per line). 

There are several issues with processing such small numbers (2e-318) in awk.

• First, the input needs to be converted to a number before using it. That is usually done by adding 0. So, you need something like:

   val=0+$1 

• Second, Normal double precision floats (53 bit mantissa and 11 bit exponent) The 11 bit width of the exponent allows the representation of numbers between 10e-308 and 10e308, so, normal floats will not be able to represent such numbers.

   $ echo '1e-307 1e-308' | awk '{print $1,$1+0,$2,$2+0}' 1e-307 1e-307 1e-308 0 

Default GNU awk will not accept (normal) values below 1e-308.

• Third, The default conversion format for awk (both CNVFMT and OFMT) are set to "%.6g". Numbers with more than 6 significant figures will be truncated. To get more significant figures: ask for them. Like %.15g for 15 (don't ask for more than 17 for a 53 bit mantissa, it could lie).

• Fourth, It is better to set the first value of max to the first input. Setting max to 0 will fail if input has a negative maximum.

If you are using GNU awk and it has been compiled with arbitrary precision you can use:

$ printf '%s\n' 2e-318 2e-317 2e-307 2e-308 2e-319 | awk -M -v PREC=100 'BEGIN{OFMT="%.15g"}; {val=0+$1}; NR==1{max=val}; {print($1,val,max)}; val>max{max=val} END{print max}' 2e-318 2e-318 2e-318 2e-317 2e-317 2e-318 2e-307 2e-307 2e-317 2e-308 2e-308 2e-307 2e-319 2e-319 2e-307 2e-307 

Or simplified to your use case:

awk -M -v PREC=100 ' BEGIN{OFMT="%.15g"}; # allow more than 6 figures {val=0+$1}; # convert input to a (float) number. NR==1{max=val}; # On the first line, set the max value. val>max{max=val} # On every entry keep track of the max. END{print max} # At the end, print the max. ' file # file with input (one per line).