Re: unexpected result using '>='

Adding

    print "\n", $in_view - $period, "\n";
[download]

after your current print line tells a story:

Content-type: text/html

239.6 ::239.6<br>
2.8421709430404e-014
0 ::239.6<br>
239.6
[download]

DWIM is Perl's answer to Gödel

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Re^2: unexpected result using '>=' by jonnyfolk (Vicar) on Aug 16, 2006 at 23:18 UTC
I see, thanks How can I force the calculation to calculate to 2 decimal places only - I've tried sprintf but the result is still in discrepancy.	[reply]
Re^3: unexpected result using '>=' by ysth (Canon) on Aug 16, 2006 at 23:47 UTC
You mean something like `$period - $in_view > .01` instead of `$period >= $in_view`? By the way, it's just a matter of time till you burn yourself by misinterpreting the sense of an `unless`. Some people recommend never using `unless`; I think it's ok so long as the expression is a single simple variable.	[reply] [d/l] [select]
Re^4: unexpected result using '>=' by GrandFather (Saint) on Aug 16, 2006 at 23:51 UTC
~~I'd be inclined to use `abs ($period - $in_view) > 0.01`.~~ /me slaps forehead. That's good for not equal, but ain't so good for `>=`! (thanks ysth). DWIM is Perl's answer to Gödel	[reply] [d/l] [select]
Re^3: unexpected result using '>=' by GrandFather (Saint) on Aug 16, 2006 at 23:27 UTC
You could use `ge` rather than `>=` which stringises the values. Your original code then prints: `Content-type: text/html 119.8 ::239.6<br>` [download] DWIM is Perl's answer to Gödel	[reply] [d/l] [select]
Re^4: unexpected result using '>=' by Thelonius (Priest) on Aug 17, 2006 at 16:31 UTC
But you almost never want to use ge for comparing numbers. For example, `my $x = 3; my $y = 20; if ($x ge $y) { print "$x ge $y\n"; }` [download] will print "3 ge 20".	[reply] [d/l]
Re^4: unexpected result using '>=' by jonnyfolk (Vicar) on Aug 16, 2006 at 23:33 UTC
Many thanks for that - much closer to what I was expecting to see! I shall read up on the difference between `>=` and `ge` in the morning (it's now 1:30am CET!)	[reply] [d/l] [select]