From 56bcea8b75df9f0bacc6c1bb0a6323d8c81e27d5 Mon Sep 17 00:00:00 2001
From: Andrew Davidson <andrew@amdavidson.com>
Date: Fri, 26 Jun 2020 15:32:21 -0400
Subject: [PATCH 1/4] finished exercise 1.5

---
 Work/bounce.py | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Work/bounce.py b/Work/bounce.py
index 3660ddd82..b609a0be0 100644
--- a/Work/bounce.py
+++ b/Work/bounce.py
@@ -1,3 +1,13 @@
 # bounce.py
 #
 # Exercise 1.5
+
+current_height = 100
+bounce_factor = 3 / 5
+bounce_number = 1
+
+
+while bounce_number <= 10:
+    current_height = current_height * bounce_factor
+    print(bounce_number, round(current_height, 4))
+    bounce_number += 1

From 771d346580eae8c379c8d389a7d9bffbbe1cb301 Mon Sep 17 00:00:00 2001
From: Andrew Davidson <andrew@amdavidson.com>
Date: Fri, 26 Jun 2020 20:38:33 -0400
Subject: [PATCH 2/4] finished exercise 1.11

---
 Work/mortgage.py | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/Work/mortgage.py b/Work/mortgage.py
index d527314e3..35a1030f1 100644
--- a/Work/mortgage.py
+++ b/Work/mortgage.py
@@ -1,3 +1,29 @@
 # mortgage.py
 #
 # Exercise 1.7
+
+principal = 500000.0
+rate = 0.05
+payment = 2684.11
+extra_payment = 1000
+extra_payment_start_month = 61
+extra_payment_end_month = 108
+total_paid = 0.0
+month = 1
+
+while principal > 0:
+    if month <= extra_payment_end_month and month >= extra_payment_start_month:
+        monthly_payment = payment + extra_payment
+    else:
+        monthly_payment = payment
+    principal = principal * (1 + rate / 12)
+    if principal >= monthly_payment:
+        principal = principal - monthly_payment
+    else:
+        monthly_payment = principal
+        principal = 0
+    total_paid = total_paid + monthly_payment
+    print(month, total_paid, principal)
+    month += 1
+
+print("Total paid", total_paid)

From 9947cc02fcd0c736c3249bd47822f6a46c09ce66 Mon Sep 17 00:00:00 2001
From: Andrew Davidson <andrew@amdavidson.com>
Date: Fri, 26 Jun 2020 21:12:12 -0400
Subject: [PATCH 3/4] finished exercise 1.28

---
 Work/pcost.py | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/Work/pcost.py b/Work/pcost.py
index e68aa20b4..14f4b5879 100644
--- a/Work/pcost.py
+++ b/Work/pcost.py
@@ -1,3 +1,16 @@
 # pcost.py
 #
 # Exercise 1.27
+
+import os
+import gzip
+
+total_cost = 0
+
+with gzip.open("Data/portfolio.csv.gz", "rt") as f:
+    next(f)
+    for l in f:
+        [shares, price] = l.split(",")[1:]
+        total_cost = total_cost + int(shares) * float(price)
+
+print(total_cost)

From 9ec4c7b8ce07d482b2a7a652b9843c4334465f04 Mon Sep 17 00:00:00 2001
From: Andrew Davidson <andrew@amdavidson.com>
Date: Fri, 26 Jun 2020 21:31:08 -0400
Subject: [PATCH 4/4] exercise 1.32 complete

---
 Work/pcost.py | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/Work/pcost.py b/Work/pcost.py
index 14f4b5879..65f90c298 100644
--- a/Work/pcost.py
+++ b/Work/pcost.py
@@ -3,14 +3,23 @@
 # Exercise 1.27
 
 import os
-import gzip
+import csv
 
-total_cost = 0
 
-with gzip.open("Data/portfolio.csv.gz", "rt") as f:
-    next(f)
-    for l in f:
-        [shares, price] = l.split(",")[1:]
-        total_cost = total_cost + int(shares) * float(price)
+def portfolio_cost(filename):
+    "returns total cost of the portfolio from filename"
+    total_cost = 0
+    with open(filename, "rt") as f:
+        rows = csv.reader(f)
+        next(rows)
+        for l in rows:
+            try:
+                [shares, price] = l[1:]
+                total_cost = total_cost + int(shares) * float(price)
+            except:
+                print("Could not parse:", l)
+    return total_cost
 
-print(total_cost)
+
+total_cost = portfolio_cost("Data/missing.csv")
+print("Total cost:", total_cost)