Hi, I made the following Go program (main.go). But it is still slower than awk or cut. I know that `cut` uses string manipulation tricks to make it run very efficiently.
https://github.com/coreutils/coreutils/blob/master/src/cut.c But I am not sure how to do the same thing in golang. Could anybody let me know what is wrong with my go program and how to make it run faster? $ ./main_.sh time ./main.go 10 < "$infile" > /dev/null real 0m1.418s user 0m0.976s sys 0m0.433s time cut -f 10 < "$infile" > /dev/null real 0m0.249s user 0m0.219s sys 0m0.026s time awk -v FS='\t' -v OFS='\t' -e '{ print $10 }' < "$infile" > /dev/null real 0m1.156s user 0m1.123s sys 0m0.031s ==> main.go <== #!/usr/bin/env gorun // vim: set noexpandtab tabstop=2: package main import ( "bufio" "fmt" "os" "strings" "strconv" ) func main() { idx, _ := strconv.Atoi(os.Args[1]) col := idx - 1 scanner := bufio.NewScanner(os.Stdin) for scanner.Scan() { line := strings.TrimRight(scanner.Text(), "\n") fields := strings.Split(line, "\t") fmt.Printf("%s\n", fields[col]) } } ==> main_.sh <== #!/usr/bin/env bash # vim: set noexpandtab tabstop=2: set -v infile=$(mktemp) seq 10000000 | paste -s -d $'\t\t\t\t\t\t\t\t\t\n' > "$infile" time ./main.go 10 < "$infile" > /dev/null time cut -f 10 < "$infile" > /dev/null time awk -v FS='\t' -v OFS='\t' -e '{ print $10 }' < "$infile" > /dev/null -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
