📄 ch02.html
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<div align="center"><tt><font size="+1">cos(x)</font></tt></div>
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<div align="center"><font size="+1">cosine of <i>x</i> (in radians)</font></div>
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<div align="center"><tt><font size="+1">tan(x)</font></tt></div>
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<div align="center"><font size="+1">tangent of <i>x</i> (in radians)</font></div>
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<div align="center"><tt><font size="+1">exp(x)</font></tt></div>
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<div align="center"><font size="+1">e<sup><i>x</i></sup></font></div>
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<div align="center"><tt><font size="+1">log(x)</font></tt></div>
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<div align="center"><font size="+1">(natural log) ln(<i>x</i>), <i>x</i>
> 0</font></div>
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<div align="center"><tt><font size="+1">log10(x)</font></tt></div>
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<div align="center"><font size="+1">(decimal log) lg(<i>x</i>), <i>x</i>
> 0</font></div>
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<div align="center"><tt><font size="+1">ceil(x)</font></tt></div>
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<div align="center"><font size="+1">smallest integer >= <i>x</i></font></div>
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<div align="center"><tt><font size="+1">floor(x)</font></tt></div>
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<div align="center"><font size="+1">largest integer <= <i>x</i></font></div>
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<div align="center"><tt><font size="+1">fabs(x)</font></tt></div>
</td>
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<div align="center"><font size="+1">absolute value |<i>x</i>|</font></div>
</td>
</tr>
</table></blockquote>
<h2>Arithmetic (Analyzing an Expression)</h2>
<P><img src="images/analyze-expression.png">
<h2>Strings</h2>
<ul>
<li><font size="+1">To use the <tt>string</tt> type, include the header file
for <tt>string</tt>s: <tt>#include<string></tt>.</font></li>
<li><font size="+1">C++ <tt>string</tt>s are enclosed in quotes, which are not
part of the <tt>string</tt>.</font></li>
<li><font size="+1">The string type behaves like number types with respect to
declaration, assignment, output and input:</font>
<blockquote>
<pre><font size="+1">string name = "John"; // declaration and initialization
name = "Carl"; // assignment
cout << "Please enter your name:"; // output
cin >> name; // input (stops at first space)</font></pre>
</blockquote></li>
<LI><font size="+1">Use the statement </font>
<blockquote><font size="+1"><tt>getline(cin, name);</tt></font></blockquote>
<font size="+1">to read all keystrokes until the <tt>Enter</tt> key; e.g.
should the user type </font>
<blockquote><font size="+1"><tt>Harry Hacker</tt></font></blockquote>
</ul>
<h2>Strings (Member Functions)</h2>
<ul>
<li><font size="+1">The number of characters in a string is called the <i>length</i>
of the string.</font></li>
<li><font size="+1">You can compute the length of the string using the <tt>length()</tt>
function.</font></li>
<li><font size="+1">The length function is a <i>member function</i>, and must
be invoked using the <i>dot notation</i>. </font></li>
</ul>
<blockquote>
<table border="1" cellpadding="4" bgcolor="black">
<tr bgcolor="#00FFFF">
<td>
<div align="center"><font size="+1"><b>Name</b></font></div>
</td>
<td>
<div align="center"><font size="+1"><b>Purpose</b></font></div>
</td>
</tr>
<tr bgcolor="white">
<td>
<div align="center"><font size="+1"><tt>s.length()</tt></font></div>
</td>
<td>
<div align="center"><font size="+1">The length of <tt>s</tt></font></div>
</td>
</tr>
<tr bgcolor="white">
<td>
<div align="center"><font size="+1"><tt>s.substr(i, n)</tt></font></div>
</td>
<td>
<div align="center"><font size="+1">The substring of length <tt>n</tt>
of <tt>s</tt> starting at index <tt>i</tt></font></div>
</td>
</tr>
<tr bgcolor="white">
<td>
<div align="center"><font size="+1"><tt>getline(f, s)</tt></font></div>
</td>
<td>
<div align="center"><font size="+1">Read <tt>string</tt> <tt>s</tt> from
the input stream <tt>f</tt></font></div>
</td>
</tr>
</table>
</blockquote>
<h2>Strings (Syntax 2.9 : Member Function Call)</h2>
<table border="1" cellpadding="4" bgcolor="#00FFFF">
<tr>
<td bgcolor="#FFFFFF">
<p><font size="+1" color="#00FFFF">Syntax 2.9 : Member Function Call</font></p>
<pre><font size="+1"><i>expression</i>.<i>function_name</i>(<i>expression</i><sub>1</sub>,<i>expressioun</i><sub>2</sub>, ..., <i>expression</i><sub>n</sub>)</font></pre>
<table border="0" cellpadding="4">
<tr>
<td valign="top"><font size="+1" color="#00FFFF">Example:</font><font size="+1">
</font></td>
<td>
<pre><font size="+1">name.length()
name.substr(0, n - 1)</font></pre>
</td>
</tr>
<tr>
<td><font size="+1" color="#00FFFF">Purpose:</font><font size="+1">
</font></td>
<td><font size="+1">The result of calling a function and supplying the
values for the function parameters.</font></td>
</tr>
</table>
<p>
</td>
</tr>
</table>
<h2>Strings (Substrings)</h2>
<ul>
<li><font size="+1">The <tt>substr(start, length)</tt> member function is used
to extract substrings. </font>
<blockquote>
<pre><font size="+1">string greeting = "Hello, World!\n";
string sub = greeting.substr(0,4);
/* sub is "Hell" */</font></pre>
</blockquote>
</li>
<li><font size="+1">The position numbers in a string start at 0. The last character
is always one less than the length of the string. </font>
<blockquote>
<table border="1" cellpadding="4" bgcolor="black">
<tr bgcolor="white">
<td width="20" bgcolor="#00ffff">
<div align="center"><tt><font size="+1">H</font></tt></div>
</td>
<td width="20" bgcolor="#00ffff">
<div align="center"><tt><font size="+1">e</font></tt></div>
</td>
<td width="20" bgcolor="#00ffff">
<div align="center"><tt><font size="+1">l</font></tt></div>
</td>
<td width="20" bgcolor="#00ffff">
<div align="center"><tt><font size="+1">l</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">o</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">,</font></tt></div>
</td>
<td width="20">
<div align="center"><font size="+1"><tt></tt> </font></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">W </font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">o</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">r</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">l</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">d</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">!</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">\n</font></tt></div>
</td>
</tr>
<tr bgcolor="white">
<td width="20">
<div align="center">0</div>
</td>
<td width="20">
<div align="center">1</div>
</td>
<td width="20">
<div align="center">2</div>
</td>
<td width="20">
<div align="center">3</div>
</td>
<td width="20">
<div align="center">4</div>
</td>
<td width="20">
<div align="center">5</div>
</td>
<td width="20">
<div align="center">6</div>
</td>
<td width="20">
<div align="center">7</div>
</td>
<td width="20">
<div align="center">8</div>
</td>
<td width="20">
<div align="center">9</div>
</td>
<td width="20">
<div align="center">10</div>
</td>
<td width="20">
<div align="center">11</div>
</td>
<td width="20">
<div align="center">12</div>
</td>
<td width="20">
<div align="center">13</div>
</td>
</tr>
</table>
</blockquote>
<LI><font size="+1"><tt>string w = greeting.substr(7, 5); </tt></font>
<blockquote>
<table border="1" cellpadding="4" bgcolor="black">
<tr bgcolor="white">
<td width="20">
<div align="center"><tt><font size="+1">H</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">e</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">l</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">l</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">o</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">,</font></tt></div>
</td>
<td width="20">
<div align="center"><font size="+1"><tt></tt> </font></div>
</td>
<td width="20" bgcolor="#00FFFF">
<div align="center"><tt><font size="+1">W </font></tt></div>
</td>
<td width="20" bgcolor="#00FFFF">
<div align="center"><tt><font size="+1">o</font></tt></div>
</td>
<td width="20" bgcolor="#00FFFF">
<div align="center"><tt><font size="+1">r</font></tt></div>
</td>
<td width="20" bgcolor="#00FFFF">
<div align="center"><tt><font size="+1">l</font></tt></div>
</td>
<td width="20" bgcolor="#00FFFF">
<div align="center"><tt><font size="+1">d</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">!</font></tt></div>
</td>
<td width="20">
<div align="center"><tt><font size="+1">\n</font></tt></div>
</td>
</tr>
<tr bgcolor="white">
<td width="20">
<div align="center">0</div>
</td>
<td width="20">
<div align="center">1</div>
</td>
<td width="20">
<div align="center">2</div>
</td>
<td width="20">
<div align="center">3</div>
</td>
<td width="20">
<div align="center">4</div>
</td>
<td width="20">
<div align="center">5</div>
</td>
<td width="20">
<div align="center">6</div>
</td>
<td width="20">
<div align="center">7</div>
</td>
<td width="20">
<div align="center">8</div>
</td>
<td width="20">
<div align="center">9</div>
</td>
<td width="20">
<div align="center">10</div>
</td>
<td width="20">
<div align="center">11</div>
</td>
<td width="20">
<div align="center">12</div>
</td>
<td width="20">
<div align="center">13</div>
</td>
</tr>
</table>
</blockquote>
</ul>
<h2>Strings (Concatenation)</h2>
<ul>
<li><font size="+1">The + operator concatenates two strings. </font>
<blockquote>
<pre><font size="+1">string fname = "Harry";
string lname = "Hacker";
string name = fname + " " + lname;</font></pre>
</blockquote>
</li>
<li><font size="+1">One or both strings surrounding the + must be a variable.</font>
</ul>
<h2>Strings (initials.cpp)</h2>
<iframe src="code/initials.cpp.html" width="80%" height="80%">Your browser does not support the iframe tag</iframe>
<P>
<h2>Strings (Output Formatting)</h2>
<ul>
<li><font size="+1">To <i>format</i> output we use the <i>manipulators</i> accessed
by including <tt>#include<iomanip></tt>.</font></li>
<li><font size="+1">The <tt>setw()</tt> manipulator sets the field width of
the next output.</font></li>
<li><font size="+1">The <tt>setprecision()</tt> manipulator is used to set the
precision of the next floating point number.</font></li>
<li><font size="+1">By using the <tt>fixed</tt> manipulator, you ensure that
trailing zeroes are displayed.</font></li>
<li><font size="+1">The sequence of commands</font>
<blockquote>
<pre><font size="+1">cout << fixed << setprecision(2);
cout << setw(8) << pennies << " "
<< setw(8) << pennies * 0.01 << "\n";
cout << setw(8) << nickles<< " "
<< setw(8) << nickles * 0.05<< "\n";
cout << setw(8) << dimes<< " "
<< setw(8) << dimes * 0.1 << "\n";
cout << setw(8) << quarters<< " "
<< setw(8) << quarters * 0.25 << "\n";</font></pre>
</blockquote>
<font size="+1">creates the table </font>
<blockquote>
<pre><font size="+1"> 1 0.01
12 0.60
4 0.40
120 30.00</font></pre>
</blockquote>
</li>
</ul>
</body>
</html>
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