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echo multiple variable with calculation

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# 1  
Old 03-11-2011
echo multiple variable with calculation
Code:
$total=500
echo "scale=2; $val1*100/$total" | bc
echo "scale=2; $val2*100*100/$total" | bc 
echo "scale=2; $val3*100/$total" | bc

I want to make the above code to be accomplish in a single echo line.
For instance output:
Code:
21.3, 44.2, 51.6

How to achieve that, some one please help, i just start learning shell script.
# 2  
Old 03-11-2011
There're many way to achieve that,here is a intuitive way to do that,redirect the output to a pipe,then replace all "newline" with ",",then use another pipeline to remove the restore the last newline.
Code:
{
  8    echo "scale=2; $val1*100/$total" | bc
  9    echo "scale=2; $val2*100*100/$total" | bc
 10    echo "scale=2; $val3*100/$total" | bc
 11 } | tr "\n" ',' | sed 's/,$/\n/'

# 3  
Old 03-11-2011
Quote:
Originally Posted by homeboy
Code:
{
  8    echo "scale=2; $val1*100/$total" | bc
  9    echo "scale=2; $val2*100*100/$total" | bc
 10    echo "scale=2; $val3*100/$total" | bc
 11 } | tr "\n" ',' | sed 's/,$/\n/'

May i know why got curly bracket?
# 4  
Old 03-11-2011
the {} defined a namespace,or say code blocks.It groups the codes inside it as a unit.so all output of the code within {} will be redirected to a pipe.
# 5  
Old 03-11-2011
Quote:
Originally Posted by homeboy
the {} defined a namespace,or say code blocks.It groups the codes inside it as a unit.so all output of the code within {} will be redirected to a pipe.
I'm sorry i cant get it, i can't get it. If like the this how to run ? is it a function type?
Code:
{
     echo "scale=2; $val1*100/$total" | bc
     echo "scale=2; $val2*100*100/$total" | bc
     echo "scale=2; $val3*100/$total" | bc
} | tr "\n" ',' | sed 's/,$/\n/'

# 6  
Old 03-11-2011
No,it not a function,have you ever learned C?like the while statement.However,the {} is a un-named code blocks here.It just reunion some codes into a space(a local space).One important usage is to redirect it's I/O like here.
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