use Currobber\Client\Yahoo\Client;

$Client = new Client();
var_dump($Client->get('USDRUB'));

=================

class Currobber\Result\PairRateData#393 (3) {
  private $pairName =>
  string(7) "USDRUB"
  private $rate =>
  double(73.5245)
  private $date =>
  string(10) "2015-12-30"
}

use Currobber\Client\Yahoo\Client;

$Client = new Client();
var_dump($Client->getMulti(['USDRUB', 'EURRUB']));

=================

array(2) {
  [0] =>
  class Currobber\Result\PairRateData#466 (3) {
    private $pairName =>
    string(7) "USDRUB"
    private $rate =>
    double(73.5245)
    private $date =>
    string(10) "2015-12-30"
  }
  [1] =>
  class Currobber\Result\PairRateData#458 (3) {
    private $pairName =>
    string(7) "EURRUB"
    private $rate =>
    double(80.3772)
    private $date =>
    string(10) "2015-12-30"
  }
}

use Currobber\Client\Currencylayer\Client;

$accessKey = '<YOUR_API_KEY>';
$Client = new Client($accessKey);
var_dump($Client->get('USD', 'RUB', '2015-10-10'));

=================

class Currobber\Result\PairQuoteData#67 (3) {
  private $pairName =>
  string(6) "USDRUB"
  private $quote =>
  double(61.775002)
  private $date =>
  string(10) "2015-10-10"
}

use Currobber\Client\Currencylayer\Client;

$accessKey = '<YOUR_API_KEY>';
$Client = new Client($accessKey);
var_dump($Client->getMulti('USD', ['EUR', 'RUB'], '2015-10-10'));

=================

array(2) {
  [0] =>
  class Currobber\Result\PairQuoteData#67 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $quote =>
    double(0.880398)
    private $date =>
    string(10) "2015-10-10"
  }
  [1] =>
  class Currobber\Result\PairQuoteData#65 (3) {
    private $pairName =>
    string(6) "USDRUB"
    private $quote =>
    double(61.775002)
    private $date =>
    string(10) "2015-10-10"
  }
}

use Currobber\Client\GrandTrunk\Client;

$Client = new Client();
var_dump($Client->get('USD', 'EUR', '2015-10-10'));

=================

array(1) {
  [0] =>
  class Currobber\Result\PairRateData#432 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $rate =>
    double(0.880365000003)
    private $date =>
    string(10) "2015-10-10"
  }
}

use Currobber\Client\GrandTrunk\Client;

$Client = new Client();
var_dump($Client->getForPeriod('USD', 'EUR', '2015-10-10', '2015-10-15'));
array(6) {
  [0] =>
  class Currobber\Result\PairRateData#432 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $rate =>
    double(0.880365000003)
    private $date =>
    string(10) "2015-10-10"
  }
  [1] =>
  class Currobber\Result\PairRateData#434 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $rate =>
    double(0.880365000003)
    private $date =>
    string(10) "2015-10-11"
  }
  [2] =>
  class Currobber\Result\PairRateData#437 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $rate =>
    double(0.879275477007)
    private $date =>
    string(10) "2015-10-12"
  }
  [3] =>
  class Currobber\Result\PairRateData#430 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $rate =>
    double(0.879198171268)
    private $date =>
    string(10) "2015-10-13"
  }
  [4] =>
  class Currobber\Result\PairRateData#429 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $rate =>
    double(0.876424189308)
    private $date =>
    string(10) "2015-10-14"
  }
  [5] =>
  class Currobber\Result\PairRateData#433 (3) {
    private $pairName =>
    string(6) "USDEUR"
    private $rate =>
    double(0.87420229041)
    private $date =>
    string(10) "2015-10-15"
  }
}