---json
{
    "page_id": "42eqvev2e75kbs58gegga"
}
---
====== How to generate a number with the Regular Expression Generator? ======


===== About =====
This howto will show you how to generate a number with the [[:docs:generator:regexp|Regular Expression Generator]].

===== Steps =====

==== The regular expression ====


The following [[:docs:generator:regexp#expression|expression]] will generate a double:
```
[0-9]{3}\.[0-9]{3}
```
where:
  * `[0-9]{3}` asks for 3 digits
  * `\.` print a point
    * Note: `\` is the escape character that tells the generator to take the dot character and not the [[kb>lang:regexp:dot|regular expression dot matcher]].
  * `[0-9]{3}` asks for 3 digits


==== Create a generator ====


The [[:docs:resource:generator|generator]] would be then:
<unit>
<file yml generator/regexp--generator.yml>
kind: generator
spec:
  maxRecordCount: 30
  columns:
    - name: regexp_double
      type: Double
      precision: 6
      scale: 3
      data-supplier:
        type: regexp
        arguments:
          expression: '[0-9]{3}\.[0-9]{3}'
          # optional seed
          seed: 12345L

</file>
</unit>

==== Print the result ====

This generator would yield the following data:
<unit>
<code bash>
tabul data print generator/regexp--generator.yml@howto
</code>
</unit>
<console height="300px" scroll="toggle">
regexp_double
-------------
      453.377
      203.849
      813.079
      865.495
      390.441
      709.933
      255.284
       19.755
      261.175
      264.911
      133.327
      394.021
      614.462
      573.909
       86.925
      753.268
      457.839
      176.918
      393.803
      833.487
       582.82
       551.98
      810.125
      802.251
      783.176
      940.763
      817.757
       17.065
       320.67
      709.529
</console>