JSON valid numerical param in Perl

Question

my $client = new JSON::RPC::Client;

$client->ua->credentials(
 'localhost:8332', 'jsonrpc', 'user' => 'password'  
  );

my $uri = 'http://localhost:8332/';
my $obj = {
  method  => 'sendfrom',
  params  => [$account,$sendto,$btc,6], };

my $res = $client->call( $uri, $obj );

if ($res){
  if ($res->is_error) { print "Error : ", $res->error_message; }
  else { print Dumper($res->result); }
} else {
  print $client->status_line;
 }

Considering the code above $btc is accepted as a param if it is declared:

$btc = 0.01;

Not accepted if it is:

$btc = 0.01;
$btc = sprintf('%.8f', $btc);

Also not accepted if it is:

&ReadParse(*data);
$btc =  $data{'amount'};

I get "500 internal server" error

Answer 1

Use 0.0 + sprintf('%.8f', $btc), 0.0 + $data{'amount'}