Skip to content

Tutorial: First run

What you’ll do

By the end of this tutorial you will:

  1. Install MORS and download the required data
  2. Create a Star and compute evolutionary tracks
  3. Inspect available tracks + units
  4. Plot one track
  5. Find stellar values at specific ages
  6. Save and reload the result

Time/units cheat sheet: Mstar in M☉, Age in Myr, Prot in days, Omega in Ω☉.

0) Prerequisites

You need:

  • Python 3 environment with pip
  • A working internet connection (for downloading data once)

Optional: Create and activate a Conda environment (requires conda installed): 

conda create -n mors python=3.11 -y
conda activate mors

No conda? create and activate a virtual environment (venv): 

python -m venv .venv
source .venv/bin/activate

1) Install MORS

pip install fwl-mors

Quick sanity check: 

python -c "import mors; print('mors imported:', mors.__version__ if hasattr(mors,'__version__') else 'ok')"

2) Download stellar evolution data

MORS requires stellar evolution tracks (downloaded once): 

mors download all

See where data are stored: 

mors env

If you want to place data somewhere else, set FWL_DATA (optional): 

export FWL_DATA=/path/to/your/data

3) Create your first star

Create a 1 M☉ star with an initial rotation period of 2.7 days (at ~1 Myr): 

import mors
star = mors.Star(Mstar=1.0, Prot=2.7)

Alternative: specify initial rotation as Ω/Ω☉: 

star = mors.Star(Mstar=1.0, Omega=10.0)

4) Inspect what tracks exist

Print track names and units: 

star.PrintAvailableTracks()
print("Lx units:", star.Units.get("Lx"))

You can access arrays either via the Tracks dict: 

age = star.Tracks["Age"]
lx  = star.Tracks["Lx"]
or via convenience attributes: 
age = star.AgeTrack
lx  = star.LxTrack

5) Plot a track

import matplotlib.pyplot as plt

plt.plot(star.AgeTrack, star.LxTrack)
plt.xlabel(f"Age [{star.Units['Age']}]")
plt.ylabel(f"Lx [{star.Units['Lx']}]")
plt.show()

If you see a plot and no errors, your installation + data are working.

6) Find stellar values at specific ages

Use the generic accessor: 

print(star.Value(Age=150.0, Quantity="Lx"))

Or a convenience method (when available): 

print(star.Lx(150.0))

7) (Optional) Try percentiles: slow/medium/fast rotators

This uses the built-in model distribution: 

slow   = mors.Star(Mstar=1.0, percentile="slow")    # 5th percentile
medium = mors.Star(Mstar=1.0, percentile="medium")  # 50th percentile
fast   = mors.Star(Mstar=1.0, percentile="fast")    # 95th percentile

print("slow percentile:", slow.percentile)
print("fast percentile:", fast.percentile)

Save: 

star.Save(filename="star.pickle")

Reload later: 

import mors
star2 = mors.Load("star.pickle")
print(star2.Lx(150.0))