15_conditionals2.sh (955B)
1 #!/bin/sh 2 3 # The previous if-conditionals were string comparisons. We will now take 4 # a look into using number comparisons. 5 # 6 # -eq # equal to 7 # -ne # not equal to 8 # -gt # greater than 9 # -ge # greater than or equal to 10 # -lt # less than 11 # -le # less than or equal to 12 # 13 # Also, when you input a number from the 'read' command, it 14 # automatically becomes a integer. Shell cannot use float or doubles. 15 # To use decimal numbers, you must delegate it to other tools that will 16 # be taught much later 17 # 18 # $ read user_input 19 # $ if [ $1 -eq 1412 ]; then 20 # $ echo "Correct pin" 21 # $ fi 22 # 23 # You can also do operations but these must be surrounded by double 24 # parenthesis. 25 # 26 # $ $((10 + 2)) # 12 addition 27 # $ $((10 - 2)) # 8 subtraction 28 # $ $((10 * 2)) # 20 multiplication 29 # $ $((10 / 2)) # 5 division 30 # $ $((-10 % 3)) # -1 modulo, finds out the remainder 31 # 32 # Write a script that tells you if an inputted number is even or odd. 33 34 num=$1 35 36 echo "odd" 37 echo "even"