Calculate interest rates with a shell script
If you put your cash to a bank account, you will want to know how much money you get with a certain amount at a given rate within a given period. Save the following Bash script as /usr/local/bin/loancalc (or something like that), make it executable, and you will be able to calculate the return on your investments with a single one-liner.
#!/bin/bash function calc() { return $(echo "scale=$2; $1" | bc) } if [ "$1" == "-h" ] || [ "$1" == "--help" ]; then echo "$0 calculates the interest loan of a given amount with a given rate for a given duration." echo "Usage: $0 AMOUNT RATE DURATION" exit 0 fi if [ -z "$3" ]; then echo "Please enter the amount, the rate and the duration (in this order)." exit 1 fi AMOUNT=$1 ZINS=$2 DURATION=$3 echo "Investment: $AMOUNT bucks at a rate of $ZINS% for $DURATION years." echo " Loan Total" for i in $(seq 1 $DURATION); do INTERESTLOAN=$(echo "scale=10; ($AMOUNT/100)*$ZINS" | bc) AMOUNT=$(echo "scale=10; $AMOUNT+$INTERESTLOAN" | bc) printf "Year ${i} %8.2f " $INTERESTLOAN; printf " %14.2f\n" $AMOUNT; done printf "Final amount: %1.2f bucks.\n" $AMOUNT
For example:
you@yourmachine ~ $ loancalc 3000 3.5 5
Investment: 3000 bucks at a rate of 3.5% for 5 years.
Loan Total
Year 1 105.00 3105.00
Year 2 108.68 3213.68
Year 3 112.48 3326.15
Year 4 116.42 3442.57
Year 5 120.49 3563.06
Final amount: 3563.06 bucks.
