mirror of
https://github.com/Brandon-Rozek/website.git
synced 2024-11-26 18:13:59 -05:00
137 lines
4.5 KiB
HTML
137 lines
4.5 KiB
HTML
|
<!DOCTYPE html>
|
||
|
<html>
|
||
|
<head>
|
||
|
<meta charset="utf-8" />
|
||
|
<meta name="author" content="Fredrik Danielsson, http://lostkeys.se">
|
||
|
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
||
|
<meta name="robots" content="noindex" />
|
||
|
<title>Brandon Rozek</title>
|
||
|
<link rel="stylesheet" href="themes/bitsandpieces/styles/main.css" type="text/css" />
|
||
|
<link rel="stylesheet" href="themes/bitsandpieces/styles/highlightjs-github.css" type="text/css" />
|
||
|
</head>
|
||
|
<body>
|
||
|
|
||
|
<aside class="main-nav">
|
||
|
<nav>
|
||
|
<ul>
|
||
|
<li class="menuitem ">
|
||
|
<a href="index.html%3Findex.html" data-shortcut="">
|
||
|
Home
|
||
|
</a>
|
||
|
</li>
|
||
|
<li class="menuitem ">
|
||
|
<a href="index.html%3Fcourses.html" data-shortcut="">
|
||
|
Courses
|
||
|
</a>
|
||
|
</li>
|
||
|
<li class="menuitem ">
|
||
|
<a href="index.html%3Flabaide.html" data-shortcut="">
|
||
|
Lab Aide
|
||
|
</a>
|
||
|
</li>
|
||
|
<li class="menuitem ">
|
||
|
<a href="index.html%3Fpresentations.html" data-shortcut="">
|
||
|
Presentations
|
||
|
</a>
|
||
|
</li>
|
||
|
<li class="menuitem ">
|
||
|
<a href="index.html%3Fresearch.html" data-shortcut="">
|
||
|
Research
|
||
|
</a>
|
||
|
</li>
|
||
|
<li class="menuitem ">
|
||
|
<a href="index.html%3Ftranscript.html" data-shortcut="">
|
||
|
Transcript
|
||
|
</a>
|
||
|
</li>
|
||
|
</ul>
|
||
|
</nav>
|
||
|
</aside>
|
||
|
<main class="main-content">
|
||
|
<article class="article">
|
||
|
<h1>Lecture in CPSC 220 Sept 25 2017</h1>
|
||
|
<h2>Constants</h2>
|
||
|
<p>Adding the keyword <code>final</code> in front of a variable declaration makes the variable constant. Meaning you cannot later change it in the code.</p>
|
||
|
<pre><code class="language-java">final int MAX = 10;</code></pre>
|
||
|
<p>By industry norm, the style of the variable is to have it in all caps.</p>
|
||
|
<p>You CANNOT do the following</p>
|
||
|
<pre><code class="language-java">final int MAX = 10;
|
||
|
MAX = 15;</code></pre>
|
||
|
<h2>Using Libraries</h2>
|
||
|
<ol>
|
||
|
<li>Import the library</li>
|
||
|
<li>Find the method that is appropriate</li>
|
||
|
<li>Use it</li>
|
||
|
</ol>
|
||
|
<p>Example:</p>
|
||
|
<pre><code class="language-java">import java.util.Math;
|
||
|
public class MathTest {
|
||
|
public static void main(String[] args) {
|
||
|
double answer = Math.ceil(5.4);
|
||
|
System.out.println(Math.ceil(4.5));
|
||
|
}
|
||
|
}</code></pre>
|
||
|
<h2>Typecasting / Type Conversions</h2>
|
||
|
<p>You can only cast a variable if you are casting it to a type that is larger than the one it was previously. The expression Polack used is that you cannot fit into super skinny jeans, but you can fit into bigger pants.</p>
|
||
|
<pre><code class="language-java">double dnum;
|
||
|
float fnum;
|
||
|
int inum;
|
||
|
dnum = (double)fnum * (double)inum;</code></pre>
|
||
|
<h2>Char vs String</h2>
|
||
|
<p><code>String</code>s are initialized in Java with double quotes while <code>char</code>s are initialized with single quotes</p>
|
||
|
<pre><code class="language-java">char initial = 'j';
|
||
|
String name = "Jennifer";</code></pre>
|
||
|
<p>Characters can be read in as an integer.</p>
|
||
|
<h2>Random Numbers</h2>
|
||
|
<ol>
|
||
|
<li>Import <code>java.util.Random;</code></li>
|
||
|
<li>Declare the random number generator</li>
|
||
|
<li>Initialize with <code>new</code></li>
|
||
|
<li>Use it</li>
|
||
|
</ol>
|
||
|
<pre><code class="language-java">import java.util.Random;
|
||
|
public class RandTest {
|
||
|
public static void main(String[] args) {
|
||
|
Random rand;
|
||
|
rand = new Random();
|
||
|
int number = rand.nextInt(100); // Random generates number between 0-99
|
||
|
}
|
||
|
}</code></pre>
|
||
|
<p>How do you generate numbers in a different range? [50, 150]</p>
|
||
|
<pre><code class="language-java">rand.nextInt(100); // 0-99
|
||
|
rand.nextInt(101) // 0 - 100
|
||
|
rand.nextInt(101) + 50 //50-150</code></pre>
|
||
|
<p>In more general terms</p>
|
||
|
<pre><code class="language-java">rand.nextInt(end - start + 1) + start</code></pre>
|
||
|
</article>
|
||
|
</main>
|
||
|
|
||
|
<script src="themes/bitsandpieces/scripts/highlight.js"></script>
|
||
|
<script src="themes/bitsandpieces/scripts/mousetrap.min.js"></script>
|
||
|
<script type="text/x-mathjax-config">
|
||
|
MathJax.Hub.Config({
|
||
|
tex2jax: {
|
||
|
inlineMath: [ ['$','$'], ["\\(","\\)"] ],
|
||
|
processEscapes: true
|
||
|
}
|
||
|
});
|
||
|
</script>
|
||
|
|
||
|
<script type="text/javascript"
|
||
|
src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
|
||
|
</script>
|
||
|
<script>
|
||
|
hljs.initHighlightingOnLoad();
|
||
|
|
||
|
document.querySelectorAll('.menuitem a').forEach(function(el) {
|
||
|
if (el.getAttribute('data-shortcut').length > 0) {
|
||
|
Mousetrap.bind(el.getAttribute('data-shortcut'), function() {
|
||
|
location.assign(el.getAttribute('href'));
|
||
|
});
|
||
|
}
|
||
|
});
|
||
|
</script>
|
||
|
|
||
|
</body>
|
||
|
</html>
|