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# dgeiger's solution

## to Space Age in the Delphi Pascal Track

Published at Aug 27 2020 · 0 comments
Instructions
Test suite
Solution

Given an age in seconds, calculate how old someone would be on:

• Mercury: orbital period 0.2408467 Earth years
• Venus: orbital period 0.61519726 Earth years
• Earth: orbital period 1.0 Earth years, 365.25 Earth days, or 31557600 seconds
• Mars: orbital period 1.8808158 Earth years
• Jupiter: orbital period 11.862615 Earth years
• Saturn: orbital period 29.447498 Earth years
• Uranus: orbital period 84.016846 Earth years
• Neptune: orbital period 164.79132 Earth years

So if you were told someone were 1,000,000,000 seconds old, you should be able to say that they're 31.69 Earth-years old.

If you're wondering why Pluto didn't make the cut, go watch this youtube video.

## Testing

In order to run the tests for this track, you will need to install DUnitX. Please see the installation instructions for more information.

If Delphi is properly installed, and `*.dpr` file types have been associated with Delphi, then double clicking the supplied `*.dpr` file will start Delphi and load the exercise/project. `control + F9` is the keyboard shortcut to compile the project or pressing `F9` will compile and run the project.

Alternatively you may opt to start Delphi and load your project via. the `File` drop down menu.

### When Questions Come Up

We monitor the Pascal-Delphi support room on gitter.im to help you with any questions that might arise.

### Submitting Exercises

Note that, when trying to submit an exercise, make sure the exercise file you're submitting is in the `exercism/delphi/<exerciseName>` directory.

For example, if you're submitting `ubob.pas` for the Bob exercise, the submit command would be something like `exercism submit <path_to_exercism_dir>/delphi/bob/ubob.pas`.

## Source

Partially inspired by Chapter 1 in Chris Pine's online Learn to Program tutorial. http://pine.fm/LearnToProgram/?Chapter=01

## Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you may request help from a mentor.

### uSpaceAgeTests.pas

``````unit uSpaceAgeTests;

interface
uses
DUnitX.TestFramework;

const
CanonicalVersion = '1.2.0';

type

[TestFixture]
SpaceAgeTests = class(TObject)
public
[Test]
//    [Ignore('Comment the "[Ignore]" statement to run the test')]
procedure Age_on_earth;

[Test]
[Ignore]
procedure Age_on_mercury;

[Test]
[Ignore]
procedure Age_on_venus;

[Test]
[Ignore]
procedure Age_on_mars;

[Test]
[Ignore]
procedure Age_on_jupiter;

[Test]
[Ignore]
procedure Age_on_saturn;

[Test]
[Ignore]
procedure Age_on_uranus;

[Test]
[Ignore]
procedure Age_on_neptune;
end;

implementation
uses uSpaceAge;

{ SpaceAgeTests }

procedure SpaceAgeTests.Age_on_earth;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(1000000000);
expectedAge := 31.69;
Assert.AreEqual(expectedAge, MyAge.OnEarth);
end;

procedure SpaceAgeTests.Age_on_jupiter;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(901876382);
expectedAge := 2.41;
Assert.AreEqual(expectedAge, MyAge.OnJupiter);
end;

procedure SpaceAgeTests.Age_on_mars;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(2129871239);
expectedAge := 35.88;
Assert.AreEqual(expectedAge, MyAge.OnMars);
end;

procedure SpaceAgeTests.Age_on_mercury;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(2134835688);
expectedAge := 280.88;
Assert.AreEqual(expectedAge, MyAge.OnMercury);
end;

procedure SpaceAgeTests.Age_on_neptune;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(1821023456);
expectedAge := 0.35;
Assert.AreEqual(expectedAge, MyAge.OnNeptune);
end;

procedure SpaceAgeTests.Age_on_saturn;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(2000000000);
expectedAge := 2.15;
Assert.AreEqual(expectedAge, MyAge.OnSaturn);
end;

procedure SpaceAgeTests.Age_on_uranus;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(1210123456);
expectedAge := 0.46;
Assert.AreEqual(expectedAge, MyAge.OnUranus);
end;

procedure SpaceAgeTests.Age_on_venus;
var
MyAge: ISpaceAge;
expectedAge: double;
begin
MyAge := NewSpaceAge(189839836);
expectedAge := 9.78;
Assert.AreEqual(expectedAge, MyAge.OnVenus);
end;

initialization
TDUnitX.RegisterTestFixture(SpaceAgeTests);
end.``````
``````unit uSpaceAge;

interface

uses
Math;

const
SecondsPerEarthYear = 31557600;

JupiterYear =  11.862615;
MarsYear    =   1.8808158;
MercuryYear =   0.2408467;
NeptuneYear = 164.79132;
SaturnYear  =  29.447498;
UranusYear  =  84.016846;
VenusYear   =   0.61519726;

type
ISpaceAge = class

private
Age: Double;

public
function OnEarth: Double;
function OnJupiter: Double;
function OnMars: Double;
function OnMercury: Double;
function OnNeptune: Double;
function OnSaturn: Double;
function OnUranus: Double;
function OnVenus: Double;

end;

function NewSpaceAge(AgeInSeconds: UInt64): ISpaceAge;

implementation

{ SpaceAges }

function ISpaceAge.OnEarth: Double;
begin
// The Earth age is already stored, so we just return it as the new age.
Result := RoundTo(Age, -2);
end;

function ISpaceAge.OnJupiter: Double;
begin
// Divide the Earth age by the number of Earth years per Jupiter year and return the
// new age.
Result := RoundTo(Age / JupiterYear, -2);
end;

function ISpaceAge.OnMars: Double;
begin
// Divide the Earth age by the number of Earth years per Mars year and return the
// new age.
Result := RoundTo(Age / MarsYear, -2);
end;

function ISpaceAge.OnMercury: Double;
begin
// Divide the Earth age by the number of Earth years per Mercury year and return the
// new age.
Result := RoundTo(Age / MercuryYear, -2);
end;

function ISpaceAge.OnNeptune: Double;
begin
// Divide the Earth age by the number of Earth years per Neptune year and return the
// new age.
Result := RoundTo(Age / NeptuneYear, -2);
end;

function ISpaceAge.OnSaturn: Double;
begin
// Divide the Earth age by the number of Earth years per Saturn year and return the
// new age.
Result := RoundTo(Age / SaturnYear, -2);
end;

function ISpaceAge.OnUranus: Double;
begin
// Divide the Earth age by the number of Earth years per Uranus year and return the
// new age.
Result := RoundTo(Age / UranusYear, -2);
end;

function ISpaceAge.OnVenus: Double;
begin
// Divide the Earth age by the number of Earth years per Venus year and return the
// new age.
Result := RoundTo(Age / VenusYear, -2);
end;

function NewSpaceAge(AgeInSeconds: UInt64): ISpaceAge;
var
ASpaceAge: ISpaceAge;
begin
// Let's create a new ISpaceAge object.
ASpaceAge := ISpaceAge.Create;

// Since the tests are only looking for two decimal places, we'll convert the
// age in seconds to Earth years to save execution time later.
ASpaceAge.Age := AgeInSeconds / SecondsPerEarthYear;

// Return the ISpaceAge object
Result := ASpaceAge;
end;

end.``````