Dtyjlui

#!/bin/bash

var1="23:30" # 11:30pm

var2="20:00" # 08:00pm



echo "$(expr $var1 - $var2)"

./test 

expr: non-integer argument

./test 

3.5

#!/bin/bash

var1="23:30" # 11:30pm

var2="20:00" # 08:00pm



echo "$(expr $var1 - $var2)"

./test 

expr: non-integer argument

./test 

3.5

#!/bin/bash

var1="23:30" # 11:30pm

var2="20:00" # 08:00pm



echo "$(expr $var1 - $var2)"

./test 

expr: non-integer argument

./test 

3.5

#!/bin/bash

var1="23:30" # 11:30pm

var2="20:00" # 08:00pm



echo "$(expr $var1 - $var2)"

./test 

expr: non-integer argument

./test 

3.5

add a comment | 

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#!/bin/bash

var1="23:30"

var2="20:00"



# Convert to epoch time and calculate difference.

difference=$(( $(date -d "$var1" "+%s") - $(date -d "$var2" "+%s") ))



# Divide the difference by 3600 to calculate hours.

echo "scale=2 ; $difference/3600" | bc

$ ./test.bash

3.50

#!/bin/bash

var1="23:30"

var2="20:00"



# Convert to epoch time and calculate difference.

difference=$(( $(date -d "$var1" "+%s") - $(date -d "$var2" "+%s") ))



# Divide the difference by 3600 to calculate hours.

echo "scale=2 ; $difference/3600" | bc

$ ./test.bash

3.50

#!/bin/bash

var1="23:30"

var2="20:00"



# Convert to epoch time and calculate difference.

difference=$(( $(date -d "$var1" "+%s") - $(date -d "$var2" "+%s") ))



# Divide the difference by 3600 to calculate hours.

echo "scale=2 ; $difference/3600" | bc

$ ./test.bash

3.50

#!/bin/bash

var1="23:30"

var2="20:00"



# Convert to epoch time and calculate difference.

difference=$(( $(date -d "$var1" "+%s") - $(date -d "$var2" "+%s") ))



# Divide the difference by 3600 to calculate hours.

echo "scale=2 ; $difference/3600" | bc

$ ./test.bash

3.50

add a comment | 

#!/bin/bash



# first time is the first argument, or 23:30     

var1=${1:-23:30}

# second time is the second argument, or 20:00

var2=${2:-20:00}



# Split variables on `:` and insert pieces into arrays

IFS=':' read -r -a t1 <<< "$var1"

IFS=':' read -r -a t2 <<< "$var2"



# strip leading zeros (so it's not interpreted as octal

t1=("${t1[@]##0}")

t2=("${t2[@]##0}")



# check if the first time is before the second one

if (( t1[0] > t2[0] || ( t1[0] == t2[0] && t1[1] > t2[1]) ))

then

  # if the minutes on the first time are less than the ones on the second time

  if (( t1[1] < t2[1] ))

  then

    # add 60 minutes to time 1

    (( t1[1] += 60 ))

    # and subtract an hour

    (( t1[0] -- ))

  fi

  # now subtract the hours and the minutes

  echo $((t1[0] -t2[0] )):$((t1[1] - t2[1]))

  # to get a decimal result, multiply the minutes by 100 and divide by 60

  echo $((t1[0] -t2[0] )).$(((t1[1] - t2[1])*100/60))

else

  echo "Time 1 should be after time 2" 2>&1

fi

$ ./script.sh 

3:30

3.50



$ ./script.sh 12:10 11:30

0:40

0.66



$ ./script.sh 12:00 11:30

0:30

0.50

#!/bin/bash



# first time is the first argument, or 23:30     

var1=${1:-23:30}

# second time is the second argument, or 20:00

var2=${2:-20:00}



# Split variables on `:` and insert pieces into arrays

IFS=':' read -r -a t1 <<< "$var1"

IFS=':' read -r -a t2 <<< "$var2"



# strip leading zeros (so it's not interpreted as octal

t1=("${t1[@]##0}")

t2=("${t2[@]##0}")



# check if the first time is before the second one

if (( t1[0] > t2[0] || ( t1[0] == t2[0] && t1[1] > t2[1]) ))

then

  # if the minutes on the first time are less than the ones on the second time

  if (( t1[1] < t2[1] ))

  then

    # add 60 minutes to time 1

    (( t1[1] += 60 ))

    # and subtract an hour

    (( t1[0] -- ))

  fi

  # now subtract the hours and the minutes

  echo $((t1[0] -t2[0] )):$((t1[1] - t2[1]))

  # to get a decimal result, multiply the minutes by 100 and divide by 60

  echo $((t1[0] -t2[0] )).$(((t1[1] - t2[1])*100/60))

else

  echo "Time 1 should be after time 2" 2>&1

fi

$ ./script.sh 

3:30

3.50



$ ./script.sh 12:10 11:30

0:40

0.66



$ ./script.sh 12:00 11:30

0:30

0.50

#!/bin/bash



# first time is the first argument, or 23:30     

var1=${1:-23:30}

# second time is the second argument, or 20:00

var2=${2:-20:00}



# Split variables on `:` and insert pieces into arrays

IFS=':' read -r -a t1 <<< "$var1"

IFS=':' read -r -a t2 <<< "$var2"



# strip leading zeros (so it's not interpreted as octal

t1=("${t1[@]##0}")

t2=("${t2[@]##0}")



# check if the first time is before the second one

if (( t1[0] > t2[0] || ( t1[0] == t2[0] && t1[1] > t2[1]) ))

then

  # if the minutes on the first time are less than the ones on the second time

  if (( t1[1] < t2[1] ))

  then

    # add 60 minutes to time 1

    (( t1[1] += 60 ))

    # and subtract an hour

    (( t1[0] -- ))

  fi

  # now subtract the hours and the minutes

  echo $((t1[0] -t2[0] )):$((t1[1] - t2[1]))

  # to get a decimal result, multiply the minutes by 100 and divide by 60

  echo $((t1[0] -t2[0] )).$(((t1[1] - t2[1])*100/60))

else

  echo "Time 1 should be after time 2" 2>&1

fi

$ ./script.sh 

3:30

3.50



$ ./script.sh 12:10 11:30

0:40

0.66



$ ./script.sh 12:00 11:30

0:30

0.50

#!/bin/bash



# first time is the first argument, or 23:30     

var1=${1:-23:30}

# second time is the second argument, or 20:00

var2=${2:-20:00}



# Split variables on `:` and insert pieces into arrays

IFS=':' read -r -a t1 <<< "$var1"

IFS=':' read -r -a t2 <<< "$var2"



# strip leading zeros (so it's not interpreted as octal

t1=("${t1[@]##0}")

t2=("${t2[@]##0}")



# check if the first time is before the second one

if (( t1[0] > t2[0] || ( t1[0] == t2[0] && t1[1] > t2[1]) ))

then

  # if the minutes on the first time are less than the ones on the second time

  if (( t1[1] < t2[1] ))

  then

    # add 60 minutes to time 1

    (( t1[1] += 60 ))

    # and subtract an hour

    (( t1[0] -- ))

  fi

  # now subtract the hours and the minutes

  echo $((t1[0] -t2[0] )):$((t1[1] - t2[1]))

  # to get a decimal result, multiply the minutes by 100 and divide by 60

  echo $((t1[0] -t2[0] )).$(((t1[1] - t2[1])*100/60))

else

  echo "Time 1 should be after time 2" 2>&1

fi

$ ./script.sh 

3:30

3.50



$ ./script.sh 12:10 11:30

0:40

0.66



$ ./script.sh 12:00 11:30

0:30

0.50

add a comment |