Boston Python workshop 2/Friday tutorial: Difference between revisions

So far, the code we've written has been <i>unconditional</i>: no choice is getting made, and the code is always run. Python has another data type called a <b>boolean</b> that is helpful for writing code that makes decisions. There are two booleans: <code>True</code> and <code>False</code>:

You can test if Python objects are equal or unequal:

Use <code>==</code> to test for equality. Recall that <code>=</code> is used for <i>assignment</i> (e.g. <code>my_string == "Hello"</code>).

<code>=</code> is assignment, <code>==</code> is comparison.

Use <code>!=</code> to test for inequality:

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"a" != "a"

</pre>

<pre>

"a" != "A"

</pre>

<code>&lt;</code>, <code>&lt;=</code>, <code>&gt;</code>, and <code>&gt;=</code> have the same meaning as in math class:

<pre>

1 > 0

</pre>

<pre>

2 >= 3

</pre>

<pre>

-1 < 0

</pre>

<pre>

.5 <= 1

</pre>

You can check for containment with the <code>in</code> keyword:

</pre>

Or check for a lack of containment with <code>not in</code>:

<pre>

"Elvis" not in "Elvis has left the building"