[SOLVED] BASH

Garrett85 · 01-13-2013, 02:54 PM

In the script I'M writting below I can't get STR hold a string, it always does an output as empty.

Code:

#! /bin/bash -x

# Program to take a user numerical input number and return it as a sentence.
#
#
#
### ARRAYS ###
ARRAY1=("" "one" "two" "three" "four" "five" "six" "seven" "eight" "nine")

ARRAY2=("" "eleven" "twelve" "thirteen" "fourteen" "fifteen" "sixteen" "seventeen" "eightteen" "nineteen")

ARRAY3=("" "ten" "tweenty" "thirty" "forty" "fifty" "sixty" "seventy" "eighty" "ninety")

ARRAY4=("" "" "thoudand" "million" "billion")

##############################
### FUNCTION-leading_zeros ###
##############################

leading_zeros() {
	local NUM=${1}
	local NUMBEROFDIGITS=${2}
	local NUMBEROFGROUPS=${3}

	while [[ $(( ${#NUM} / 3 )) -ne ${NUMBEROFGROUPS} ]] || [[ ${#NUM} -lt 3  ]]; do
		NUM="0${NUM}"
	done

	echo ${NUM}
}

read -p "Enter a number no higher than the billions range" NUM

NUMBEROFDIGITS=${#NUM}
NUMBEROFGROUPS=$(( NUMBEROFDIGITS / 3 ))

if [[ ${NUMBEROFDIGITS} -lt 3 ]]; then # {
	NUMBEROFGROUPS=1
	NUM=$( leading_zeros ${NUM} ${NUMBEROFDIGITS} ${NUMBEROFGROUPS})
elif [[ $(( NUMBEROFDIGITS % 3 )) -ne 0 ]]; then # } {
	let NUMBEROFGROUPS=NUMBEROFGROUPS+1
	NUM=$( leading_zeros ${NUM} ${NUMBEROFDIGITS} ${NUMBEROFGROUPS})
fi # }

STR=""
STARTPOINT=0
while [[ ${NUMBEROFGROUPS} -gt 0 ]]; do # {
	CURRENTGROUP=${NUM:${STARTPOINT}:3}
	D1=${CURRENTGROUP:0:1}
	D2=${CURRENTGROUP:1:1}
	D3=${CURRENTGROUP:2:1}

	if [[${D1} -eq 0 ]]; then # {
		if [[ ${D2} -eq 0 ]] && [[ ${D3} -ne 0 ]]; then # {
			STR="${STR} ${ARRAY1[D3]} ${ARRAY4[NUMBEROFGROUPS]}"

		fi # }
	fi # }
	echo "${D1} ${D2} $D3}"
	let STARTPOINT=STARTPOINT+3
	let NUMBEROFGROUPS=NUMBEROFGROUPS-1
done # }

echo ${NUM}

echo "The string is ${STR}"

kbp · 01-13-2013, 04:46 PM

There are a couple of typos but it seems to work logically exactly as specified, I've added comments to clarify:

Code:

...
#kbp: make STR an empty string
STR=""
STARTPOINT=0
while [[ ${NUMBEROFGROUPS} -gt 0 ]]; do # {
    CURRENTGROUP=${NUM:${STARTPOINT}:3}
    D1=${CURRENTGROUP:0:1}
    D2=${CURRENTGROUP:1:1}
    D3=${CURRENTGROUP:2:1}

    #kbp: if the number entered has a leading zero...
    if [[ ${D1} -eq 0 ]]; then # {
        #kbp: .. and if the second digit is a zero and the the third digit isn't ...
        if [[ ${D2} -eq 0 ]] && [[ ${D3} -ne 0 ]]; then
            #kbp: ... set STR
            STR="${STR} ${ARRAY1[D3]} ${ARRAY4[NUMBEROFGROUPS]}"
        fi
    fi
    echo "${D1} ${D2} $D3"

STR will only be set to a non-empty string if the number entered is in the format: 00[1-9] .. is this what you wanted?

Garrett85 · 01-13-2013, 07:33 PM

Why does it need to be in the format 00[1-9]? Each part of the three digit numbe is broken down into it's own variable D#. Why is STR not getting the string values from the ARRAYs?

Quote:

Originally Posted by kbp

There are a couple of typos but it seems to work logically exactly as specified, I've added comments to clarify:

Code:

...
#kbp: make STR an empty string
STR=""
STARTPOINT=0
while [[ ${NUMBEROFGROUPS} -gt 0 ]]; do # {
    CURRENTGROUP=${NUM:${STARTPOINT}:3}
    D1=${CURRENTGROUP:0:1}
    D2=${CURRENTGROUP:1:1}
    D3=${CURRENTGROUP:2:1}

    #kbp: if the number entered has a leading zero...
    if [[ ${D1} -eq 0 ]]; then # {
        #kbp: .. and if the second digit is a zero and the the third digit isn't ...
        if [[ ${D2} -eq 0 ]] && [[ ${D3} -ne 0 ]]; then
            #kbp: ... set STR
            STR="${STR} ${ARRAY1[D3]} ${ARRAY4[NUMBEROFGROUPS]}"
        fi
    fi
    echo "${D1} ${D2} $D3"

STR will only be set to a non-empty string if the number entered is in the format: 00[1-9] .. is this what you wanted?

kbp · 01-13-2013, 07:48 PM

Because those are the conditions imposed by the 'if' loops you wrote. Let me write your logic into an english sentence:

If the first digit is zero then check if the second digit is zero and that the third digit is not zero - if all of these tests are true then make STR equal to the concatenation of what STR is now and ARRAY1[D3] and ARRAY4[NUMBEROFGROUPS].

If any of the tests fail then we drop out without setting STR .. got it ?

<edit>This is only the case for 3 digit numbers...</edit>