# Logstash Ruby not handling float value correctly
**URL:** https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150
**Category:** Logstash
**Created:** [October 23, 2020, 2:35pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150 "2020-10-23T14:35:40Z")
**Posts on this page:** 8
**Page:** 1
### Author:  [@mastersmit](https://discuss.elastic.co/u/mastersmit)
#### Post date: [October 23, 2020, 2:35pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/1 "2020-10-23T14:35:41Z")
I have Kafak \<\> Logstash (then Ruby) \<\> Elastic
Kafak Input:
```auto
{"customerid":"smit","last_name":"shah","age":10,"height":10,"weight":100,"automated_email":false, "header": { "endpoint":"/pay"}, "transaction": { "amount":100.50, "currency" : "SGD"}}
```
Logstash:
```auto
json {
source => "message"
}
mutate {
convert => { "amount" => "float" }
}
ruby {
# Cancel 90% of events
path => "/usr/local/etc/logstash/main.rb"
script_params => { "percentage" => 0.9 }
}
}
```
Ruby
```auto
transaction = event.get('transaction')
puts transaction
puts transaction['amount']
```
This prints:
```auto
{"amount"=>0.1005e3, "currency"=>"SGD"}
0.1005e3
```
Why I am not getting 100.5?
---
### Author:  [@Badger](https://discuss.elastic.co/u/Badger)
#### Post date: [October 23, 2020, 3:35pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/2 "2020-10-23T15:35:07Z")
> [@mastersmit](#):
>
> Why I am not getting 100.5?
ruby likes to print floats in exponential form. You can tell it not to using sprintf formatting strings such as %5.1f
---
### Author:  [@mastersmit](https://discuss.elastic.co/u/mastersmit)
#### Post date: [October 23, 2020, 5:04pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/3 "2020-10-23T17:04:36Z")
Thanks. Thats solved the issue partially.
I have added this: `amazing_var = sprintf('%f',transaction['amount'])`
It is printing `100.500000` Is it possible for it to not format to padding zero and keep exact value.
Note: It is not known the no. of decimal points in the input.
---
### Author:  [@Badger](https://discuss.elastic.co/u/Badger)
#### Post date: [October 23, 2020, 5:11pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/4 "2020-10-23T17:11:32Z")
I suggest you use mutate+gsub to remove the trailing zeroes.
---
### Author:  [@mastersmit](https://discuss.elastic.co/u/mastersmit)
#### Post date: [October 25, 2020, 1:09pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/5 "2020-10-25T13:09:47Z")
@Badger Here is the code I am planning on using, do you suggest any better way to write this:
```auto
amount = "1234.50000"
def filtered_amount(amount)
decimal_amt = amount.split('.', -1)[1]
after_index = -1
for i in 0..decimal_amt.length - 1
current_char = decimal_amt[i]
if current_char == '0' && after_index == -1
after_index = i
elsif current_char != '0'
after_index = -1
end
end
first_part = decimal_amt[0..after_index]
return amount.split('.', -1)[0] << "." << first_part
end
puts "Before: " << amount
puts "After: " << filtered_amount(amount)
```
Output:
```auto
$ruby main.rb
Before: 1234.50000
After: 1234.50
```
As I believe this will take up too much of processing time. Any Suggestion?
---
### Author:  [@Badger](https://discuss.elastic.co/u/Badger)
#### Post date: [October 25, 2020, 2:15pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/6 "2020-10-25T14:15:43Z")
If you always want two digits after the period I would use mutate, not ruby
```
mutate { gsub => ["amount", "(\.\d\d)0+", "\1"] }
```
---
### Author:  [@mastersmit](https://discuss.elastic.co/u/mastersmit)
#### Post date: [October 25, 2020, 3:31pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/7 "2020-10-25T15:31:07Z")
Nope, my usecase does not have a fixed length after `dot`. However thanks for the code snippet. Appreciate it.
---
### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [November 22, 2020, 3:31pm UTC](https://discuss.elastic.co/t/logstash-ruby-not-handling-float-value-correctly/253150/8 "2020-11-22T15:31:10Z")
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