[SOLVED] Getting the correct index from an array

[Garrett85]

I've got an array CALENDER=(31 28 31 30 31 30 31 31 30 31 30 31)

I have two if statements that Need to get an index from the array above but when I feed a value into the brackets e.g. ${CALENDER[${SECONDDIGIT}]} or ${CALENDER[${FIRSTDIGIT}]} it seems to only be getting the first inded of the CALENDER array, 31, even though FIRSTVALUE will have a number from 1-9 in it and SECONDDIGIT will have 10, 11, or 12. Any ideas by I am unable to get the correct index with my FIRST and SECONDDIGIT values? Thanks.

[Miven]

You don't need to go

${CALENDER[${SECONDDIGIT}]}

You can just go

n=1; d=${CALENDER[n]}

Which will return d=28 according to the array you presented. And don't forget leap years.

But enough of that. I'm assuming you're scripting in bash, and it would *really* help to show a code snippet so I can tell what you're trying to do and where you're going wrong. You have 2 variables, d1 and d2. d1 is 1-9 and d2 is 10-12. Fine. This array has 12 elements, but is numbered 0-11. That's how arrays work. It would seem you need to go 0-8 and 9-11 to index this array properly.

But, again, I'm assuming far too much.

Peace and cheer.

[Garrett85]

Below is the whole script. And yes, I have accounted for leap year. Thanks.

#! /bin/bash -x


# This is the calender array for the DateValidation program
CALENDER=(31 28 31 30 31 30 31 31 30 31 30 31)


#############################
### FUNCTION-is_leap_year ###
#############################

is_leap_year()
{
        PART1=`expr ${YY} % 4`
        PART2=`expr ${YY} % 100`
        if [[ 0 -eq ${PART1} ]] && [[ 0 -ne ${PART2} ]] || [[ 0 -eq `expr ${YY} % 400` ]]; then #{
                result=true
	else
		result=false
        fi #}
}


####################
### END FUNCTION ###
####################

########################
### FUNCTION-get_day ###
########################

get_day()
{
	DAY="BAD"
	FIRSTDIGIT=${MM:0:1}
	SECONDDIGIT=${MM:1:1}
	if [[ ${FIRSTDIGIT} -eq 0 ]]; then #{
		if [[ ${DD} -gt 0 ]] && [[ ${DD} -le ${CALENDER[${SECONDDIGIT+1}]} ]]; then #{
			DAY="GOOD"
		fi #}
	else
		if [[ ${DD} -gt 0 ]] && [[ ${DD} -le ${CALENDER[${MM}]} ]]; then #{
			DAY="GOOD"
		fi #}
	fi #}
}

####################
### END FUNCTION ###
####################

read -p "Enter a date for validation: " DATE

# establish the varible LEN to hold the number of characters in Date, 8 is the only valid number
LEN=$(echo ${#DATE})

if [ $LEN -eq 8 ]; then #{
 
	# set date dariables MM, DD, & YY
	MM=${DATE:0:2}
	DD=${DATE:2:2}
	YY=${DATE:4:4}

	if [ ${YY} -gt 0 ]; then #{
		if [ ${MM} -gt 0 ] && [ ${MM} -lt 13 ]; then
			if [ ${MM} -eq 02 ]; then
				
				is_leap_year ${YY} 
				if [ $result == true ]; then
					if [ ${DD} -gt 0 ] && [ ${DD} -le 29 ]; then
						echo "${DATE} is a valid date!"
					else
						echo "${DD} is incalid for this date!"
					fi #}
				else
					get_day ${DD}
					if [ ${DAY} == GOOD ]; then
						echo "${Date} is a valid date!"
					else
						echo "${DD} is invalid for this date!"
					fi #}
				fi #}
			else
				get_day ${DD}
				if [ ${DAY} == GOOD ]; then
					echo "${DD} is a valid date!"
				else
					echo "${DD} is invalid for this date!"
				fi #}
			fi #}

		else
			echo "${MM} is invalid for this date!"
		fi #}

	else
		echo "${YY} is invalid for this date!"
	fi #}
else
	echo "Invalid number of digits for a date!"
fi #}

[watael]

It would seem you need to go 0-8 and 9-11 to index this array properly.

index 0 can be filled with a fake value[code]array=( _ 31 28 ... ), this way you do not make your code heavier with arithmetics

note that Garrett85 asks here too

[Garrett85]

note that Garrett85 asks here too

I see you get around lol.