# Re: [Jprogramming] Finding Irrational Numbers

```Skip said:
Given the vector a:

]a =. % 1+i.20```
```
1 0.5 0.333333 0.25 0.2 0.166667 0.142857 0.125 0.111111 0.1 0.0909091
0.0833333 0.0769231 0.0714286 0.0666667 0.0625 0.0588235 0.0555556
0.0526316 0.05

Roger said:
Your list a are reciprocals of integers and so are all rational.

Roger also said:
All rational fractions result in infinitely repeating floating point
numbers.  They are the same sets.

Skip says:
So all the numbers in a are rational, and infinitely repeating? Like 0.5,
0.25. 0.2, 0.1? I'm confused. These examples don't seem to have infinitely
repeating decimals.

â€‹Skip

On Wed, Jun 13, 2018 at 12:44 PM Roger Hui <rogerhui.can...@gmail.com>
wrote:

> What's an irrational number in this context?  Your list a are reciprocals
> of integers and so are all rational.  On the other hand, going just by the
> display, 0.5 is a rational number (1%2), but since the display is to 6
> significant digits, for all you know 0.5 could be
> 0.500000314159265358979... (0.5+ pi*1e_7) and irrational.
>
>
> On Wed, Jun 13, 2018 at 10:29 AM, Skip Cave <s...@caveconsulting.com>
> wrote:
>
> > Here's another problem similar to my previous one about finding integers
> in
> > a floating point array:
> >
> > Find the irrational numbers in a floating-point array:
> >
> > Given the vector a:
> >
> > ]a =. % 1+i.20
> >
> > 1 0.5 0.333333 0.25 0.2 0.166667 0.142857 0.125 0.111111 0.1 0.0909091
> > 0.0833333 0.0769231 0.0714286 0.0666667 0.0625 0.0588235 0.0555556
> > 0.0526316 0.05
> >
> >
> > Create a function that will generate a boolean array indicating the
> > locations of the irrational numbers in a.
> >
> >
> > Skip
> > ----------------------------------------------------------------------
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> ----------------------------------------------------------------------
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