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Published: (January 14, 2026 at 04:09 PM EST)
1 min read
Source: Dev.to

Source: Dev.to

Bash script for filtering CSV columns

#!/bin/bash
# Usage:
#   ./filter.sh file.csv decimals col1 [col2 ... colN]
#
# Example:
#   ./filter.sh data.csv 2 45

if [ "$#" -lt 3 ]; then
    echo "Usage: $0 file.csv decimals col1 [col2 ... colN]"
    exit 1
fi

file="$1"
decimals="$2"
shift 2

cols=$(IFS=,; echo "$*")

awk -F'~' -v OFS='~' -v cols="$cols" -v dec="$decimals" '
BEGIN {
    n = split(cols, cidx, ",")

    # scaling factor: 10^dec
    scale = 1
    for (i = 1; i = 0 ? 0.5 : -0.5)) / scale

            $col = sprintf(fmt, rounded)
        }
    }
    print
}
' "$file"
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