Absolute Value Percentage Difference Question

#1

Hi.

I’ve got a report where I’m making comparisons between 2 different
values. It’s possible for the percentage difference from one value to
the next to be less than or greater than the original number.

If value 2 is 20% greater than OR 20% less than value 1, I want to
highlight that row in a table that I created.

Any thoughts on how to write the correct if statement that would yield
this result?

So far I have diff = (value1 - value2) / value1

.5 = (10-5)/10 which is a 50% decrease between the 2 values

Since the percentage difference is greate than 20%, how can I test that
50% in an if statement to highlight this difference for review?

THANKS!

#2

On Oct 20, 2008, at 4:19 PM, Becca G. wrote:

Any thoughts on how to write the correct if statement that would yield

THANKS!

def highlight_difference(value1, value2, close_enough=0.8…1.2)
return nil if value1.nil? || value2.nil?
return nil if value1.zero?
return nil if close_enough.include?(value2.to_f/value1)
true
end
irb> highlight_difference(10, 5)
=> true
irb> highlight_difference(10, 8)
=> nil
irb> highlight_difference(10, 12)
=> nil
irb> highlight_difference(10, 15)
=> true

-Rob

Rob B. http://agileconsultingllc.com