in reply to Check whether two numbers are within a range

This?


  DB<54> $b=3.1565323

  DB<55> $a=3.1566789

  DB<56> p abs(1e5*($b-$a)) <1

  DB<57> p abs(1e5*($b-$a))
14.660000000033
  DB<58>

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of course you could avoid the multiplication by providing an accurate threshold smaller than 1.

It'll become more complicated with two coordinates, than I'd say Pythagoras is accurate enough°

edit

Pythagoras sqr( d_x ** 2 + d_y ** 2 ) with d_ for delta= abs(c0-c1)

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

°) even for spherical coordinates of that size (but don't use this for the distance between New York and Seattle, you might fall off the edge of the world)

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Re^2: Check whether two numbers are within a range
by stevieb (Canon) on Feb 26, 2021 at 16:56 UTC

    Thank you. This works well, regardless if the vehicle's actual location will be plus or minus the pre-determined coordinates I'll be comparing against.

    Mock up:

    use warnings;
use strict;
use feature 'say';

use constant {
    ACCURACY    => 1e5,
    RANGE       => 1.2,
    LON         => -119.31665,
};

my $lon_current = -119.31666;

my $deviation = abs(ACCURACY * (LON - $lon_current));

say "Within range: $deviation" if $deviation < RANGE;

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[d/l]
      I hope you are not only testing the longitude but also the latitude.

      Cheers Rolf
      (addicted to the Perl Programming Language :)
      Wikisyntax for the Monastery

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