note
ikegami
<p>But such a demonstrations wasn't necessary for me since I had finished writing the following from scratch before you posted your solution. (I didn't post it since I didn't want to do the OP's homework for him.)
<c>
sub ikegami_exp {
my ($x) = @_;
my $last = 0;
my $result = 1;
my $acc = 1;
for (my $n = 1; abs($result-$last)>0; $n++) {
$last = $result;
$acc *= $x/$n;
$result += $acc;
}
return $result;
}
for (1, 0.1, 10, 3.14, 0.1234, 100) {
printf("%.16e: exp() = %.16e ikegami_exp() = %.16e\n",
$_,
exp($_),
ikegami_exp($_),
);
}
</c>
<p>The only difference was the terminating condition, so naturally, that's what interested me :) Mine goes into an infinite loop if you try to find <c>ikegami_exp(1000)</c>, but that's easily fixed by replacing <c>abs($result-$last)>0</c> with <c>$result != $last</c>.
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