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Bash rounding up numbers with printf

For eg: $NUMBEROFPASSES=6.19

to round up I use

NUMBEROFPASSES=$(printf %.0f $NUMBEROFPASSES)

What I need to do is round up from eg: 6.10 to be 7 and if lower than 6.10 round down to 6

Any help would be appreciated
Thanks
Gary

Quote:

Originally Posted by gary_in_springhill (Post 3849817)

What I need to do is round up from eg: 6.10 to be 7 and if lower than 6.10 round down to 6

From the man page for bash:

Code:

ARITHMETIC EVALUATION

      The  shell allows arithmetic expressions to be evaluated, under certain

      circumstances (see the let and declare builtin commands and  Arithmetic

      Expansion).  Evaluation  is done in fixed-width integers with no check

      for overflow, though division by 0 is trapped and flagged as an  error.

If you need floating point, you'll have to add some awk magic:

Code:

#!/bin/bash

NUMBER=6.19

NUMBER=$(echo $NUMBER | awk '{ print $0 + .90 }')

NUMBER=$(printf "%0.f" $NUMBER)

echo "NUMBER = $NUMBER"

Thanks for your reply it put me on the right track for sure, but I tested it with various numbers eg: 4.99 and it rounded to six??

Quote:

Originally Posted by gary_in_springhill (Post 3850030)

Thanks for your reply it put me on the right track for sure, but I tested it with various numbers eg: 4.99 and it rounded to six??

This survives all of your test cases

Code:

#!/bin/bash



float()

{

        # Convert the first parameter to a floating point number

        # no matter how broken the input

        VALUE=$(printf "%f" $1)

        echo $VALUE

}



greater()

{

        VALUE=$(float $1)

        CHECK=$(echo $VALUE | awk '{ result = ( $1 > 0.0 ) ; print !result }')

        return $CHECK

}



offset()

{

        VALUE=$1

        if greater $VALUE ; then

                # Adjust the rounding offset

                RESULT=$(echo $VALUE | awk '{ print 0.5 - $1 }')

        else

                # Use the standard rounding offset

                RESULT="0.0"

        fi

        echo $RESULT

}



round ()

{

        NUMBER=$1

        OFFSET=$2

        # If the offset is greater than zero

        if greater $OFFSET ; then

                # Add the non-standard rounding offset to the number

                RESULT=$(echo $NUMBER $OFFSET | awk '{ print $1 + $2 }')

        else

                # Add the standard rounding offset to the number

                RESULT=$(echo $NUMBER | awk '{ print $1 + .50 }')

        fi

        echo "$NUMBER, $OFFSET -> $(printf "%0.f" $RESULT)"

}



NUMBER=6.19

OFFSET=$(offset .10)

round $NUMBER $OFFSET

NUMBER=6.09

OFFSET=$(offset .10)

round $NUMBER $OFFSET

NUMBER=4.99

OFFSET=$(offset .00)

round $NUMBER $OFFSET

The script can probably be simplified.

how about this:

Code:

#!/bin/sh



NUM=$1



bc << EOF

num = $NUM;

base = num / 1;

if (((num - base) * 10) > 1 )

    base += 1;

print base;

EOF

echo ""

Thanks to both of you , this did the trick .
Thanks again