Dear monks,

I'm scratching my head on this string-to-number conversion. Here's the basis of the problem.

I get from a ncurses multi-box (that has 10 choices) an array of indices as to which check boxes are checked. Like this:

8 1 9

This one shows that checkboxes # 1, 8 and 9 were checked. The first checkbox of the list is # 0.

Now, I want to transfer this to two 8-bit bit-mapped numbers. The number above would yield, as a 16-bit number:

0x0302

I would like to get the following two 8-bit numbers:

0x03 0x02

Is there a way to do this without having any additional module ?

On the other hand, I tried Bit::Vector. It is a surprisingly complete module and I can do this, @sel being the array returned from the ncurses checkbox): 

  my $vector = Bit::Vector->new(16);
  $vector->Index_List_Store(@sel);
  $value = $vector->to_Hex();

[download]

Sure enough, $value = 0302. But it is a string, eg: 0x30333032.

How can I get my two bytes out of that ?

Moreover, am I making things more complicated that they should be ? This surely does not make me feel lazy ! ;-)

Thanks !

Al

In reply to Making two 8-bit numbers from indices of set bits by carcassonne

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