From 221be8caf49fdd37e0013c80d2df85f8b725860b Mon Sep 17 00:00:00 2001
From: Mark Piper <mark.piper@colorado.edu>
Date: Wed, 19 Jul 2023 13:27:25 -0600
Subject: [PATCH] Add Python script example

---
 lessons/hpc/calculate_pi.py | 27 +++++++++++++++++++++++++++
 lessons/hpc/calculate_pi.sh | 19 +++++++++++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 lessons/hpc/calculate_pi.py
 create mode 100644 lessons/hpc/calculate_pi.sh

diff --git a/lessons/hpc/calculate_pi.py b/lessons/hpc/calculate_pi.py
new file mode 100644
index 0000000..6d03b50
--- /dev/null
+++ b/lessons/hpc/calculate_pi.py
@@ -0,0 +1,27 @@
+"""Approximate pi with the Bailey-Borwein-Plouffe formula.
+
+Adapted from:
+http://blog.recursiveprocess.com/2013/03/14/calculate-pi-with-python
+"""
+
+import sys
+from decimal import Decimal
+
+
+def bailey_borwein_plouffe_formula(n):
+    pi = Decimal(0)
+    k = 0
+    while k < n:
+        pi += (Decimal(1) / (16**k)) * (
+            (Decimal(4) / (8 * k + 1))
+            - (Decimal(2) / (8 * k + 4))
+            - (Decimal(1) / (8 * k + 5))
+            - (Decimal(1) / (8 * k + 6))
+        )
+        k += 1
+    return pi
+
+
+if __name__ == "__main__":
+    for i in range(1, int(sys.argv[1])):
+        print(i, bailey_borwein_plouffe_formula(i))
diff --git a/lessons/hpc/calculate_pi.sh b/lessons/hpc/calculate_pi.sh
new file mode 100644
index 0000000..cfd91cc
--- /dev/null
+++ b/lessons/hpc/calculate_pi.sh
@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+#SBATCH --job-name=calculate_pi
+#SBATCH --output=%x_%j.out
+#
+# A job script that calls a Python script that approximates pi.
+#
+# Submit this script to the scheduler with:
+#   $ qsub calculate_pi.pbs.sh
+
+module purge
+module load anaconda/2022.10
+
+hostname
+python --version
+
+echo "Calculating pi with the Bailey-Borwein-Plouffe formula"
+echo "Start time:" `date`
+python calculate_pi.py 20
+echo "End time:" `date`