public function testBadObservationsCount()
{
$observations = new Observations();
$observations->add([1, 2, 3], 4);
static::setExpectedException('InvalidArgumentException');
$observations->add([1, 2], 4);
}
/**
* @return Observations
*/
private function getLogisticObservations()
{
// Data from http://statistics.ats.ucla.edu/stat/r/dae/logit.htm
$observations = new Observations();
$csv = fopen(__DIR__ . '/../../fixtures/logistic.csv', 'r');
fgetcsv($csv);
// Throw away headers.
while ($line = fgetcsv($csv)) {
// Split composite feature, since the school rank isn't actually an interval value.
$rank2 = $line[3] == 2 ? 1 : 0;
$rank3 = $line[3] == 3 ? 1 : 0;
$rank4 = $line[3] == 4 ? 1 : 0;
// Normalize the GRE score. This is critical to get convergence.
$gre = $line[1] / 100;
// [1, GRE, GPA, Rank2, Rank3, Rank4], Admitted
$observations->add([1, $gre, $line[2], $rank2, $rank3, $rank4], (double) $line[0]);
}
fclose($csv);
return $observations;
}
