text-shadow: 0 0 20px #333;
padding: 2px 5px;
}
+ .indexlink {
+ position: absolute;
+ bottom: 1em;
+ left: 1em;
+ }
</style>
</head>
<body>
---
+layout: true
+
+.indexlink[[Index](index.html)]
+
+---
+
# Enciphering and deciphering
## Arithmetic on letters
---
+# Using the tools
+
+Before doing anything, create a new branch in Git
+
+* This will keep your changes isolated
+
+Experiment in IPython (ephemeral, for us)
+
+Once you've got something working, copy the code into a `.py` file (permanent and reusable)
+
+```python
+from imp import reload
+
+import test
+reload(test)
+from test import *
+```
+
+Re-evaluate the second cell to reload the file into the IPython notebook
+
+When you've made progress, make a Git commit
+
+* Commit early and often!
+
+When you've finished, change back to `master` branch and `merge` the development branch
+
+---
+
# The [string module](http://docs.python.org/3.3/library/string.html) is your friend
```python
```
---
+
# DRY and YAGNI
Is your code DRY?
---
-# Doing all the letters
+# Doing the whole message
## Test-first developement
---
-# Doing all the letters
+# Doing the whole message
## Abysmal
ciphertext += caesar_encipher_letter(plaintext[i], key)
```
+Try it in IPython
+
---
-# Doing all the letters
+# Doing the whole message
## Bad
---
-# Doing all the letters
+# Doing the whole message
## Good (but unPythonic)
---
-# Doing all the letters
+# Doing the whole message
## Best
<script src="http://gnab.github.io/remark/downloads/remark-0.6.0.min.js" type="text/javascript">
</script>
<script type="text/javascript">
- var slideshow = remark.create();
+ var slideshow = remark.create({ ratio: "16:9" });
</script>
</body>
</html>
\ No newline at end of file