 The  integral  value  returned  by  these functions may be too large to store in an integer type (int, long,  etc.).   To  avoid  an  overflow, which  will  produce undefined results, an application should perform a range check on the returned value before assigning  it  to  an  integer type.

from the ceil(3) Linux man page.

That&#39;s because `float`&#39;s range is wider than `int`&#39;s. What would you expect to have if the value returned by these functions did not fit into an `int`? That would be undefined behaviour and you would be unable to check for that in your program.

    SET SERVEROUTPUT ON
    DECLARE
		v_student_id NUMBER := &amp;sv_student_id;
		v_section_id NUMBER := 89;
		v_final_grade NUMBER;
		v_letter_grade CHAR(1);
    BEGIN
		SELECT final_grade
		INTO v_final_grade
		FROM enrollment
		WHERE student_id = v_student_id
		AND section_id = v_section_id;
		
		CASE -- outer CASE
			WHEN v_final_grade IS NULL THEN
				DBMS_OUTPUT.PUT_LINE (&#39;There is no final grade.&#39;);
			ELSE
				CASE -- inner CASE
					WHEN v_final_grade &gt;= 90 THEN v_letter_grade := &#39;A&#39;;
					WHEN v_final_grade &gt;= 80 THEN v_letter_grade := &#39;B&#39;;
					WHEN v_final_grade &gt;= 70 THEN v_letter_grade := &#39;C&#39;;
					WHEN v_final_grade &gt;= 60 THEN v_letter_grade := &#39;D&#39;;
					ELSE v_letter_grade := &#39;F&#39;;
				END CASE;
				
				-- control resumes here after inner CASE terminates
				DBMS_OUTPUT.PUT_LINE (&#39;Letter grade is: &#39;||v_letter_grade);
		END CASE;
		-- control resumes here after outer CASE terminates
    END;

the above code I have taken from the book *&quot;Oracle PL/SQL by Example, 4th Edition 2009&quot;* my problem is when I enter a `student_id` not present in the table it returns me the following error

&lt;pre&gt;
Error report: ORA-01403: no data found
ORA-06512: at line 7
01403. 00000 -  &quot;no data found&quot;
*Cause:    
*Action:
&lt;/pre&gt;

but according to the book it should have returned a null value and then follow the case flow.

PL/SQL block problem: No data found error

I’m currently responsible for rolling out the use of jQuery to the community of Web Developers within our company. Part of this involves presenting a course, however another part involves communicating standards and best practice.

If you Google &#39;jQuery best practice&#39;, you’ll probably find the following among the search results.
[http://www.smashingmagazine.com/2008/09/16/jquery-examples-and-best-practices/][1]
[http://www.artzstudio.com/2009/04/jquery-performance-rules/][2]

These have been helpful and I have gleamed much useful information on them. However, what I would be really interested in would be any tips, traps, opinions, etc, on best practice from experienced jQuery developers and those who may have found themselves in a similar position to myself. Any good links would also be appreciated.

**EDIT:**

Added a jQuery Coding Standards section on my own page:

http://www.jameswiseman.com/blog/?p=48


  [1]: http://www.smashingmagazine.com/2008/09/16/jquery-examples-and-best-practices/
  [2]: http://www.artzstudio.com/2009/04/jquery-performance-rules/
  [3]: http://ejohn.org/blog/ultra-chaining-with-jquery/

jQuery Standards and Best Practice

Once in a while, I find myself rounding some numbers, and I always have to cast the result to an integer:

    int rounded = (int) floor(value);

Why do all rounding functions (`ceil()`, `floor()`) return a floating number, and not an integer? I find this pretty non-intuitive, and would love to have some explanations!

Why do round() and ceil() not return an integer?

Once in a while, I find myself rounding some numbers, and I always have to cast the result to an integer:
<pre><code class="hljs language-arduino">int rounded = (int) floor(value);
</code></pre>
Why do all rounding functions (<code>ceil()</code>, <code>floor()</code>) return a floating number, and not an integer? I find this pretty non-intuitive, and would love to have some explanations!

I want to iterate over all files in a directory matching something like `somefiles*.txt`. 

Does `boost::filesystem` have something built in to do that, or do I need a regex or something against each `leaf()`?


Can I use a mask to iterate files in a directory with Boost?

Is it possible to use the `break` function to exit several nested `for` loops?

If so, how would you go about doing this? Can you also control how many loops the `break` exits?



Can I use break to exit multiple nested &#39;for&#39; loops?

I need to iterate over `std::queue`.
www.cplusplus.com says:

&gt; By default, if no container class is specified for a particular queue class, the standard container class template deque is used.

So can I somehow get to the queue&#39;s underlying deque and iterate over it?

std::queue iteration

Which STL container would fit my needs best? I basically have a 10 elements wide container in which I continually `push_back` new elements while `pop_front` ing the oldest element (about a million time). 

I am currently using a `std::deque` for the task but was wondering if a `std::list` would be more efficient since I wouldn&#39;t need to reallocate itself (or maybe I&#39;m mistaking a `std::deque` for a `std::vector`?). Or is there an even more efficient container for my need?

P.S. I don&#39;t need random access

Which STL container should I use for a FIFO?

There seem to be different views on using &#39;using&#39; with respect to the std namespace.

Some say use &#39; `using namespace std`&#39;, other say don&#39;t but rather prefix std functions that are to be used with &#39; `std::`&#39; whilst others say use something like this:

    using std::string;
    using std::cout;
    using std::cin;
    using std::endl;
    using std::vector;

for all the std functions that are to be used.

What are the pros and cons of each?

Using std Namespace

**Edit: I&#39;ve added the source for the example.**

I came across [this example][1]:

    char source[MAX] = &quot;123456789&quot;;
	char source1[MAX] = &quot;123456789&quot;;
	char destination[MAX] = &quot;abcdefg&quot;;
	char destination1[MAX] = &quot;abcdefg&quot;;
	char *return_string;
	int index = 5;
	
    /* This is how strcpy works */
	printf(&quot;destination is originally = &#39;%s&#39;\n&quot;, destination);
	return_string = strcpy(destination, source);
	printf(&quot;after strcpy, dest becomes &#39;%s&#39;\n\n&quot;, destination);
	
	/* This is how strncpy works */
    printf( &quot;destination1 is originally = &#39;%s&#39;\n&quot;, destination1 );
    return_string = strncpy( destination1, source1, index );
    printf( &quot;After strncpy, destination1 becomes &#39;%s&#39;\n&quot;, destination1 );

Which produced this output:

&lt;pre&gt;destination is originally = &#39;abcdefg&#39;
After strcpy, destination becomes &#39;123456789&#39;
 
destination1 is originally = &#39;abcdefg&#39;
After strncpy, destination1 becomes &#39;12345fg&#39;
&lt;/pre&gt;

Which makes me wonder why anyone would want this effect. It looks like it would be confusing. This program makes me think you could basically copy over someone&#39;s name (eg. Tom Brokaw) with Tom Bro763.  

**What are the advantages of using** `strncpy()` **over** `strcpy()`?

[1]:http://publib.boulder.ibm.com/infocenter/iadthelp/v7r0/index.jsp?topic=/com.ibm.etools.iseries.langref.doc/rzan5mst269.htm

Why should you use strncpy instead of strcpy?

What does it mean and how important to know about it for a C/C++ programmers?

Is it the same across the platforms, at least conceptually?


I understand it as a block of allocated memory used to store local variable by a function...

I want to know more


What is activation record in the context of C and C++?

How can I extract an IP address into a string? I can&#39;t find a reference that tells me how `char sa_data[14]` is encoded.

Getting IPV4 address from a sockaddr structure

Is there a way in C to find out the size of dynamically allocated memory?     

For example, after

    char* p = malloc (100);

Is there a way to find out the size of memory associated with `p`?

Determine size of dynamically allocated memory in C

Can someone elaborate on the following gcc error?

    $ gcc -o Ctutorial/temptable.out temptable.c 
    temptable.c: In function ‘main’:
    temptable.c:5: error: ‘for’ loop initial declaration used outside C99 mode

temptable.c:

    ...
    /* print Fahrenheit-Celsius Table */
    main()
    {
    	for(int i = 0; i &lt;= 300; i += 20)
    	{
    		printf(&quot;F=%d C=%d\n&quot;,i, (i-32) / 9);		
    	}
    }

P.S: I vaguely recall that `int i` should be declared before a `for` loop. I should state that I am looking for an answer that gives a historical context of C standard.


C: for loop int initial declaration

I&#39;m receiving a dict from one &quot;layer&quot; of code upon which some calculations/modifications are performed before passing it onto another &quot;layer&quot;. The original dict&#39;s keys &amp; &quot;string&quot; values are `unicode`, but the layer they&#39;re being passed onto only accepts `str`.

This is going to be called often, so I&#39;d like to know what would be the fastest way to convert something like:

    { u&#39;spam&#39;: u&#39;eggs&#39;, u&#39;foo&#39;: True, u&#39;bar&#39;: { u&#39;baz&#39;: 97 } }

...to:

    { &#39;spam&#39;: &#39;eggs&#39;, &#39;foo&#39;: True, &#39;bar&#39;: { &#39;baz&#39;: 97 } }

...bearing in mind the non-&quot;string&quot; values need to stay as their original type.

Any thoughts?

Fastest way to convert a dict&#39;s keys &amp; values from `unicode` to `str`?

I was checking the behavior of dynamic_cast and found that when it fails, std::bad_cast exception is thrown only if the destination is a reference type. If the destination is a pointer type then no exception is thrown from the cast. This is my sample code:
	

    class A
    {
    	public:
    		virtual ~A()
    		{
    		}
    };
    
    class B : public A
    {
    };
    
    int  main()
    {
        A* p = new A;
        
        //Using reference
        try
        {
    	B&amp; b = dynamic_cast&lt;B&amp;&gt;(*p);
        }
        catch(std::bad_cast exp)
        {
    	std::cout&lt;&lt;&quot;Caught bad cast\n&quot;;
        }
        
        //Using pointer
          try
        {
    	B* pB = dynamic_cast&lt;B*&gt;(p);
    	
    	if( pB == NULL)
    	{
    		std::cout&lt;&lt;&quot;NULL Pointer\n&quot;;
    	}
        }
        catch(std::bad_cast exp)
        {
    	std::cout&lt;&lt;&quot;Caught bad cast\n&quot;;
        }
        
        return 0;
    }

Output is &quot;Caught bad cast&quot; and &quot;NULL pointer&quot;. Code is compiled using VS2008. Is this the correct behavior ? If yes, then why there is a difference?

Difference in behavior while using dynamic_cast with reference and pointers

I keep finding both on here and Google people having troubles going from `long` to `int` and not the other way around. Yet I&#39;m sure I&#39;m not the only one that has run into this scenario before going from `int` to `Long`.

The only other answers I&#39;ve found were &quot;Just set it as Long in the first place&quot; which really doesn&#39;t address the question.

I initially tried casting but I get a &quot;`Cannot cast from int to Long`&quot;

    for (int i = 0; i &lt; myArrayList.size(); ++i ) {
        content = new Content();
        content.setDescription(myArrayList.get(i));
        content.setSequence((Long) i);
        session.save(content);
    }

As you can imagine I&#39;m a little perplexed, I&#39;m stuck using `int` since some content is coming in as an `ArrayList` and the entity for which I&#39;m storing this info requires the sequence number as a Long.

How do I convert from int to Long in Java?

Consider the following sample code:

    class SampleClass
    {
        public long SomeProperty { get; set; }
    }

    public void SetValue(SampleClass instance, decimal value)
    {
        // value is of type decimal, but is in reality a natural number =&gt; cast
        instance.SomeProperty = (long)value;
    }


Now I need to do something similar through reflection:

    void SetValue(PropertyInfo info, object instance, object value)
    {
        // throws System.ArgumentException: Decimal can not be converted to Int64
        info.SetValue(instance, value)  
    }

Note that I cannot assume that the PropertyInfo always represents a long, neither that value is always a decimal. However, I know that value can be casted to the correct type for that property.

How can I convert the &#39;value&#39; parameter to the type represented by PropertyInfo instance through reflection ?


&#39;casting&#39; with reflection

How do I provide support for casting my class to other types? For example, if I have my own implementation of managing a `byte[]`, and I want to let people cast my class to a `byte[]`, which will just return the private member, how would I do this?

Is it common practice to let them also cast this to a string, or should I just override `ToString()` (or both)?

How do I provide custom cast support for my class?

I&#39;m making a program that, for reasons not needed to be explained, requires a float to be converted into a string to be counted with len(). However, str(float(x)) results in x being rounded when converted to a string, which throws the entire thing off. Does anyone know of a fix for it?
Here&#39;s the code being used if you want to know:

    len(str(float(x)/3))

Converting a float to a string without rounding it

How can I round down a number in JavaScript?

`math.round()` doesn&#39;t work because it rounds it to the nearest decimal. 

I&#39;m not sure if there is a better way of doing it other than breaking it apart at the decimal point at keeping the first bit. There must be...

How can I round down a number in Javascript?

I need to round a double to nearest five. I can&#39;t find a way to do it with the Math.Round function. How can I do this?

What I want:

    70 = 70
    73.5 = 75
    72 = 70
    75.9 = 75
    69 = 70

and so on..

Is there an easy way to do this?

Round to nearest five

How can we round off a number to the nearest 10 in php?

Say I have `23`, what code would I use to round it off to `30`?

How to round up a number to nearest 10?

I have this line of code which rounds my numbers to two decimal places. But I get numbers like this: 10.8, 2.4, etc. These are not my idea of two decimal places so how I can improve the following?

    Math.round(price*Math.pow(10,2))/Math.pow(10,2);

I want numbers like 10.80, 2.40, etc. Use of jQuery is fine with me.


Content Type	Original Author	Original Content on Stackoverflow
Question	Wookai	View Question on Stackoverflow
Solution 1 - C++	Sean A.O. Harney	View Answer on Stackoverflow
Solution 2 - C++	sharptooth	View Answer on Stackoverflow

Why do round() and ceil() not return an integer?

C++ Problem Overview

C++ Solutions

Solution 1 - C++

Solution 2 - C++

jQuery Standards and Best Practice

PL/SQL block problem: No data found error

Attributions