Question: I learnt that, Java allows file names to have unicode characters.

How to name a file,
`naïve.java`,
using english keyboard?

Is there a notation similar to unicode escape notation(used in java source code) that we can use to name java files with unicode characters?

Answer: 
The answer is simple 

```
>> time_f(time_f == 0.288)

ans =

   Empty matrix: 0-by-1

```

Your matrix doesn't contain the value 0.288

This is due to float precision, so instead of being 0.288, your value is 0.287999999 for example.

Just use [`roundn`](http://fr.mathworks.com/help/map/ref/roundn.html), which round to a specified number of significant digits

```
>> time_f = roundn(time_f,-3);
>> find(time_f == 0.288)

ans =

   145

```

If you don't have Mapping toolbox you can do 

```
>> time_f = round(time_f * 1000) / 1000

```
You are using floating point arithmetic, which has certain precision errors. Your matrix does not contain exactly the value 0.288.