From: Josselin <josselin@...>
Date: 2007-05-24T14:50:04+09:00
Subject: Re: printing float to string with decimal rounding

On 2007-05-23 16:34:50 +0200, Robert Klemme <shortcutter@googlemail.com> said:

> On 23.05.2007 16:24, Josselin wrote:
>> I am trying to print a float result in a string but I can get it right
>> 
>> I get float numbers like :
>> distance =  0.2568915421 , 1.2568910001,  20.3256941254   (8 decimals)
>> 
>> I wrote
>>    d = (distance.*1000).round/1000.0     # to get something like  0.257
>>    return "(- de 500m)" if d < 0.500
>>    return "( - de 1km)" if d < 1.0
>>    return "(env. " + d.to_s + " km)"
>> 
>> if d > 1.0   i print   "env. 1.257 km"
>> I'd like to print "env. 1.2 km"  shoudl I round it again ? or is there 
>> any DRY solution ?
> 
> Is this good enough?
> 
> irb(main):010:0> "%.2f" % 1.000
> => "1.00"
> irb(main):011:0> "%.2f" % 1.005
> => "1.00"
> irb(main):012:0> "%.2f" % 1.006
> => "1.01"
> 
> Your values
> 
> irb(main):007:0> [0.2568915421 , 1.2568910001,  20.3256941254].map {|f| 
> "%10.2f" % f}
> => ["      0.26", "      1.26", "     20.33"]
> irb(main):008:0> [0.2568915421 , 1.2568910001,  20.3256941254].map {|f| 
> "%.2f" % f}
> => ["0.26", "1.26", "20.33"]
> 
> Kind regards
> 
> 	robert

thanks a lot.. did not know about that...   using too much the rails helpers...
fuunny,  it's like speaking a foreign language like spanish when you 
know italian... similarities but also new stuff and slang ;-))