Decimal numbers represented by a binary system are ALWAYS rounded / subject to rounding. For example, your first number, given as 0.123456789012, is internally approximated / stored as 0.123456789011999995553381381796, which itself is a rounded value already. You may end up less than or greater than your target value, or, in rare cases, exactly on target (0.5, or 0.25, for example).
So, your request is a bit diffucult to fulfill. You can try awk's OFMT variable set to a fixed output field length, but, surprise, additional undesired decimal places occur:
If that is unsatisfying, you can resort to formatted print and a tricky taylored field length computation:
This works as there are two additional places needed for the division by 100, but length ($1) already counts two characters: the leading 0 and dot. If you have more significant leading digits, additional measures / steps need to be taken.
Hello
I am getting this very annoying issue in awk:
awk '{a=12825;b=a*1.25; print b}' test
16031.2
Thing is the multiplication result is wrong... Result should be 16031.25.
I think the issue only happens on bigger numbers.
What can I do to get passed this?
Thanks by advance (3 Replies)
Hi Friends,
I am trying to round following number.
0.07435000
echo "0.07435000"|awk '{printf "%s\n",$1*100}'|awk '{printf "%.2f\n",$1}'
It returns: 7.435
It should return: 7.44
Any suggestion please?
Thanks,
Prashant (2 Replies)
I need to read the file divide 3 column with 2nd and run a modulus of 10 and check whether the remainder is zero or not if not print the entire line.
cat filename | awk '{ if ($3 / $2 % 10 != 0) print $0}'
Whats wrong with it ? (4 Replies)
Hi,
I have managed to round up numbers by using the following command:
echo "5.54" | awk '{printf "%.0f\n", $1}'
result
6
How can I round up all the numbers in a column in a file and print the lines with the new calculated totals?
Thanks, (3 Replies)
I received error "awk: division by zero" while executing the following statement.
SunOS 5.10 Generic_142900-15 sun4us sparc FJSV,GPUZC-M
echo 8 | awk 'END {printf ("%d\n",NR/$1 + 0.5);}' file1.lst
awk: division by zero
Can someone provide solution?
Thanks
Please use code... (11 Replies)
I had a person bring an interesting problem to me that appears to involve some sort of rounding inside awk. I've verified this with awk and nawk on Solaris as well as with gawk 3.1.5 on a Linux box.
The original code fragment he brought me was thus:
for (index=0; index < 1; index=index+.1)
... (4 Replies)
vmstat|awk '{print $3}'|tail -1
returns 6250511, but what I need is 24416, which is 6250511 divided by 256.
Please advise.
Thank you so much (2 Replies)
I have some calculation in my script which is similar to the below example . I find that sometimes when using large decimal digits, the output gets automatically rounded off and it is affecting the program. I am not able to understand what is happening here..
awk '{
a=6.32498922
a1=6.324... (5 Replies)
Hi Friends,
I have an input file like this
cat input
chr1 100 200 1 2
chr1 120 130 na 1
chr1 140 160 1 na
chr1 170 180 na na
chr1 190 220 0 0
chr1 220 230 nd 1
chr2 330 400 1 nd
chr2 410 450 nd nd
chr3 500 700 1 1
I want to calculate the division of 4th and 5th columns. But, if... (3 Replies)
Heyas
Trying to calculate the total size of a file by reading its bitrate.
Code snippet:
fs_expected() { #
# Returns the expected filesize in bytes
#
pr_str() {
ff=$(cat $TMP.info)
d="${ff#*bitrate: }"
echo "${d%%,*}" | $AWK '{print $1}' | head -n 1
}
t_BYTERATE=$((... (9 Replies)
Discussion started by: sea
9 Replies
LEARN ABOUT PHP
round
ROUND(3) 1 ROUND(3)round - Rounds a floatSYNOPSIS
float round (float $val, [int $precision], [int $mode = PHP_ROUND_HALF_UP])
DESCRIPTION
Returns the rounded value of $val to specified $precision (number of digits after the decimal point). $precision can also be negative or
zero (default).
Note
PHP doesn't handle strings like "12,300.2" correctly by default. See converting from strings.
PARAMETERS
o $val
- The value to round
o $precision
- The optional number of decimal digits to round to.
o $mode
- Use one of the following constants to specify the mode in which rounding occurs.
+--------------------+---------------------------------------------------+
| Constant | |
| | |
| | Description |
| | |
+--------------------+---------------------------------------------------+
| | |
| PHP_ROUND_HALF_UP | |
| | |
| | Round $val up to $precision decimal places away |
| | from zero, when it is half way there. Making 1.5 |
| | into 2 and -1.5 into -2. |
| | |
| | |
|PHP_ROUND_HALF_DOWN | |
| | |
| | Round $val down to $precision decimal places |
| | towards zero, when it is half way there. Making |
| | 1.5 into 1 and -1.5 into -1. |
| | |
| | |
|PHP_ROUND_HALF_EVEN | |
| | |
| | Round $val to $precision decimal places towards |
| | the next even value. |
| | |
| | |
|PHP_ROUND_HALF_ODD | |
| | |
| | Round $val to $precision decimal places towards |
| | the next odd value. |
| | |
+--------------------+---------------------------------------------------+
RETURN VALUES
The rounded value
EXAMPLES
Example #1
round(3) examples
<?php
echo round(3.4); // 3
echo round(3.5); // 4
echo round(3.6); // 4
echo round(3.6, 0); // 4
echo round(1.95583, 2); // 1.96
echo round(1241757, -3); // 1242000
echo round(5.045, 2); // 5.05
echo round(5.055, 2); // 5.06
?>
Example #2
$mode examples
<?php
echo round(9.5, 0, PHP_ROUND_HALF_UP); // 10
echo round(9.5, 0, PHP_ROUND_HALF_DOWN); // 9
echo round(9.5, 0, PHP_ROUND_HALF_EVEN); // 10
echo round(9.5, 0, PHP_ROUND_HALF_ODD); // 9
echo round(8.5, 0, PHP_ROUND_HALF_UP); // 9
echo round(8.5, 0, PHP_ROUND_HALF_DOWN); // 8
echo round(8.5, 0, PHP_ROUND_HALF_EVEN); // 8
echo round(8.5, 0, PHP_ROUND_HALF_ODD); // 9
?>
Example #3
$mode with precision examples
<?php
/* Using PHP_ROUND_HALF_UP with 1 decimal digit precision */
echo round( 1.55, 1, PHP_ROUND_HALF_UP); // 1.6
echo round( 1.54, 1, PHP_ROUND_HALF_UP); // 1.5
echo round(-1.55, 1, PHP_ROUND_HALF_UP); // -1.6
echo round(-1.54, 1, PHP_ROUND_HALF_UP); // -1.5
/* Using PHP_ROUND_HALF_DOWN with 1 decimal digit precision */
echo round( 1.55, 1, PHP_ROUND_HALF_DOWN); // 1.5
echo round( 1.54, 1, PHP_ROUND_HALF_DOWN); // 1.5
echo round(-1.55, 1, PHP_ROUND_HALF_DOWN); // -1.5
echo round(-1.54, 1, PHP_ROUND_HALF_DOWN); // -1.5
/* Using PHP_ROUND_HALF_EVEN with 1 decimal digit precision */
echo round( 1.55, 1, PHP_ROUND_HALF_EVEN); // 1.6
echo round( 1.54, 1, PHP_ROUND_HALF_EVEN); // 1.5
echo round(-1.55, 1, PHP_ROUND_HALF_EVEN); // -1.6
echo round(-1.54, 1, PHP_ROUND_HALF_EVEN); // -1.5
/* Using PHP_ROUND_HALF_ODD with 1 decimal digit precision */
echo round( 1.55, 1, PHP_ROUND_HALF_ODD); // 1.5
echo round( 1.54, 1, PHP_ROUND_HALF_ODD); // 1.5
echo round(-1.55, 1, PHP_ROUND_HALF_ODD); // -1.5
echo round(-1.54, 1, PHP_ROUND_HALF_ODD); // -1.5
?>
CHANGELOG
+--------+---------------------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------------------------+
| 5.3.0 | |
| | |
| | The $mode parameter was introduced. |
| | |
| 5.2.7 | |
| | |
| | The inner workings of round(3) was changed to |
| | conform to the C99 standard. |
| | |
+--------+---------------------------------------------------+
SEE ALSO ceil(3), floor(3), number_format(3).
PHP Documentation Group ROUND(3)