Hi,

I'm pretty confused about these 4 statements ( or I'm just a blockhead in understanding the evaluation order / precedence of operators and parentheses ).

The first and third statement print a simple arithmetic opertation (using differently placed parentheses) in a float value interpreted sprintf instruction. That is ok.

But why does the second and fourth statement print different rounded values? I have no clue and don't know how to find out.

Please, could someone advise?

perl -e 'print sprintf( "%f",     66.5 * ( ( 100 + 19 ) / 100 ) ), "\n
+79.135000"'
perl -e 'print sprintf( "%.2f",   66.5 * ( ( 100 + 19 ) / 100 ) ), " <
+-- wrong, expected 79.14\n"'

perl -e 'print sprintf( "%f",     66.5 * (   100 + 19 ) / 100   ), "\n
+79.135000"'
perl -e 'print sprintf( "%.2f",   66.5 * (   100 + 19 ) / 100   ), " <
+-- ok = 79.14\n"'

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In reply to strange sprintf behavior? by oseeliger

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