[Jprogramming] Adding leading zeros

[David Porter]

Hi Skip,

Try this:

lz=: 3 : 0

,' '([,.~ -.~"1) ":10#.^:_1 y

)


      lz 1 20 300 4000 50000

00001 00020 00300 04000 50000

Good Luck,

Dave

On 2/3/2019 2:15 PM, 'Skip Cave' via Programming wrote:
> Paolo and Devon provided the named dyadic verbs Fill and lead0s that
> perform the function I specified. Devon's verb has some extra bells and
> whistles which I like.
> Roger pointed out that the built-in format function 8!:2 allows a fill
> option, but with my limited J expertise I wasn't able to turn Roger's
> example into a named dyadic verb.
> I liked R.E. Boss' approach, as it automatically sets the number of
> characters, given the number of characters in the largest integer, as that
> would work for my current problem. Again, however, I don't know how to turn
> that verb into a named monadic verb.
> All in all, I learned quite a lot from this exercise.
>
> Skip
>
>
> On Sun, Feb 3, 2019 at 2:36 AM Skip Cave <skip at caveconsulting.com> wrote:
>
>> What's the best way to add leading zeros to a set of integers. How to
>> design a verb f, that does the following:
>>
>>     a =.  1 2 3 4 5 10 20 30 40 50 100 200 300 400 500 1000 2000 3000 4000
>> 5000
>> 4 f a NB. make each integer a total of 4 digits using leading zeros.
>> 0001 0002 0003 0004 0005 0010 0020 0030 0040 0050 0100 0200 0300 0400 0500
>> 1000 2000 3000 4000 5000
>>
>> Skip
>>
>>
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