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If statement with pipeline

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# 1  
Old 10-21-2013
If statement with pipeline
Hi

Can anybody please explain me the following script in detail
Code:
Value=`echo "if ( ${FACTOR[$ROW]} >= 1 ) {1}" | bc`

What does "{1}" mean to here ?
# 2  
Old 10-21-2013
It is the statement that bc evaluates if the condition is true.

In effect it uses bc to parse the condition and return 1 if true

From the bc manual section on statements:
Quote:
if ( expression ) statement1 [else statement2]
The if statement evaluates the expression and executes statement1 or statement2 depending on the value of the expression. If the expression is non-zero, statement1 is executed. If statement2 is present and the value of the expression is 0, then statement2 is executed. (The else clause is an extension.)
# 3  
Old 10-21-2013
I wonder if the syntax is correct. Have you run whatever contains that statement? What shell are you using?
# 4  
Old 10-21-2013
Quote:
Originally Posted by blackrageous
I wonder if the syntax is correct. Have you run whatever contains that statement? What shell are you using?
It works just fine with gnu bc
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