import static org.junit.Assert.*;

import org.junit.Test;


public class TemperatureUtilTest {

  @Test
  public void test_DEG_C_PER_DEG_F() {
    final double EXP = 5.0 / 9.0;
    assertEquals(EXP, TemperatureUtil.DEG_C_PER_DEG_F, Math.ulp(EXP));
  }

  @Test
  public void test_DEG_F_PER_DEG_C() {
    final double EXP = 9.0 / 5.0;
    assertEquals(EXP, TemperatureUtil.DEG_F_PER_DEG_C, Math.ulp(EXP));
  }
  
  @Test
  public void test() {
    // some temperatures in degrees Celcius
    final double[] C = {0.0, 100.0, -40.0, -78.0, 5e100};
    
    // corresponding temperatures in degrees Fahrenheit
    final double[] F = {32.0, 212.0, -40.0, -108.4, 9e100};
    
    for (int i = 0; i < C.length; i++) {
      final double EXP_C = C[i];
      final double EXP_F = F[i];
      assertEquals(EXP_F, TemperatureUtil.celciusToFahrenheit(EXP_C), Math.ulp(EXP_F));
      assertEquals(EXP_C, TemperatureUtil.fahrenheitToCelcius(EXP_F), Math.ulp(EXP_C));
    }
  }
    
}