[indent]
When dealing with a string, an external program is many, many times slower than using shell internals.
not many times slower.... you are using echo to pipe to awk, an extra pipe process increase the time.
its just 0.003s. not that big a difference. Besides that, for an apple to apple comparison, its not even accurate. The above awk statement already had the 2nd field stored in memory and can be used anytime, whereas the shell one does not.
Quote:
I have an 80-line shell function, fpmul, which multiplies floating point numbers.
who would want to write and maintain an 80 lines code instead of one line ? your timing and my timing may differ since we may have different processors. Here's my timing:
same with bc
In the end, it doesn't really matter a big deal. The only big deal is, you write 80 lines of code to perform only a mere 0.003s difference with a one liner.
Quote:
On the contrary, complicated programs can be written in the shell that perform faster than those using another language.
that's not true . Complicated programs should not be written with shell, period. They should be written with languages like Python, or Perl with modules. There are simply many things that shell can't do very well.
Quote:
There are times when an external program is better, especially dealing with large files.
a tool that can process small and large files efficiently is still better than one that only works well on small files
Quote:
Since most people will have some familiarity with the shell, it is faster to learn to use it well than to learn a new programming language.
not really true. the shell's syntax is not exactly friendly to use. A programming language for example Python has easy to read syntax, and with that respect, reading and deciphering code is "faster", thereby easier to learn than shell.
Nowadays its not about speed of program execution, but speed of script development and easier code maintenance.
Hi,
I have input with decimal point ( 9.99 ) for hours variable hrs.
I need to change it to seconds.
Here is my code:
secs=`/usr/ucb/echo $hrs*3600 |bc`
But I don't want to see the decimal point.
I can use awk to trim it if there is one.
I am just wondering if there is better standard... (2 Replies)
Hi all. Using /bin/sh on an HPUX system.
I want to place a decimal in the field 2 charactors from the right (yes, converting to currency). The field lengths are variable. Here's what I'm doing:
exec < filename
while read FIELD1 FIELD2
do
FIELD1="echo $FIELD1 | sed 'syntax that will... (4 Replies)
Im trying to compare two numbers with decimals but its not working as expected.
a=1
b=1.1
if
then echo "equal"
fi
When I do this it says that the numbers are equal. Ultimately Im using -le and -ge in the if statements but I tested with -eq for simplicity.
Any way to make this... (3 Replies)
Hi
In Unix, I have a file with some numbers like :
45600
12345
I want to insert a decimal point for these numbers based on user input.
If the input is 2, the numbers should be changed to
456.00
123.45
If the input is 3, the numbers should be changed to
45.600
12.345
Can... (2 Replies)
For numbers between 0 and 1 the below logic is not working.
Output of above shall be "correct" but its echoing "incorrect".Kindly suggest
a=.1
if
then
echo correct
else echo incorrect
fi
Video tutorial on how to use code tags in The UNIX and Linux Forums. (3 Replies)
Hi All,
Can some one help me in identifying the significance of character "$" ,Which is playing critical role in matching decimal point numbers as below.
$ echo "01#.01"|awk '{if ($0 ~ /^+(\.*)?$/) print}'
$ echo "01#.01"|awk '{if ($0 ~ /^+(\.*)?/) print}'
01#.01
$
Regards,
Rmkganesh. (3 Replies)
Hello,
I am having a problem when i execute following script on RHEL 6.4. Same script works fine on another machine where I have same version of RHEL and KSH.
Below is the rpm and RHEL version.
ossvm12(0)> rpm -qa | grep ksh
ksh-20100621-19.el6.x86_64
ossvm12(0)> cat... (7 Replies)
Hi,
i need to move the decimal point from a file listing some numbers like this :
49899.50
49914.55
49894.48
49939.65
49879.44
49919.57
49934.62
49944.67
49954.72 (1 Reply)
Hi!
I found and then adapt the code for my pipeline...
awk -F"," -vOFS="," '{printf "%0.2f %0.f\n",$2,$4}' xxx > yyy
I add -F"," -vOFS="," (for input and output as csv file) and I change the columns and the number of decimal...
It works but I have also some problems... here my columns
... (7 Replies)
Hi , I have a file which contains text like
A|Mau|Code|12|Detail
B|Mau|Code|20|Header
I want to write a command using awk which will output
A|Mau|Code|12.00|Detail
B|Mau|Code|20.00|Header
I used a command like awk -F"|" {printf "%s|%s|%s|%.2f|%s",$1,$2,$3,$4,$5}' which does the... (4 Replies)