Number comparison gotcha

I'm using E to do some statistics on the output of some data 
temperature/light level loggers. In processing the output into 
usable form, I substituted -5000 for any missing or invalid values.

In a statistical program, I convert the string values of the 
measurements to float64 with:

   <import:java.lang.makeDouble>.parseDouble(numberAsString)

(Ugly but functional) making "value" in the example below a 
float64 number.

I included the test in a statistical program it skip missing values:

   if (value == -5000) { return }

It didn't ever compare equal. (But the program ran with no 
thrown errors.) So I changed it to:

   if (value == -5000.0) { return }

and it worked.

The lack of any error indication that the first test was wrong 
is worrying for a language that was designed to be relatively "safe".

Cheers - Bill

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