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MySQL, better to insert NULL or empty string?
...
I don't know what best practice would be here, but I would generally err in favor of the null unless you want null to mean something different from empty-string, and the user's input matches your empty-string definition.
Note that I'...
What's the purpose of using braces (i.e. {}) for a single-line if or loop?
...think of is nested if's:
if (cond1)
if (cond2)
doSomething();
Now, assume you now want to doSomethingElse() when cond1 is not met (new feature). So:
if (cond1)
if (cond2)
doSomething();
else
doSomethingElse();
which is obviously wrong, since the else associates with the ...
Why should hash functions use a prime number modulus?
...or likely cases, since collisions reduce the efficiency of the hashtable.
Now, suppose someone puts a whole bunch of values into a hashtable that have some relationship between the items, like all having the same first character. This is a fairly predictable usage pattern, I'd say, so we don't want...
Can I create more than one repository for github pages?
...using custom domain names.
(since April 2013, all username.github.com are now username.github.io)
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What do the &,
Up until now I have only used database.yml with each parameter called out explicitly, in the file below it uses some characters I do not understand. What does each line and symbol(&,*,
...
What does “dereferencing” a pointer mean?
...ate, see "More about memory addresses, and why you probably don't need to know" at the end of this answer.
When you want to access the data/value in the memory that the pointer points to - the contents of the address with that numerical index - then you dereference the pointer.
Different computer...
Converting strings to floats in a DataFrame
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NOTE: pd.convert_objects has now been deprecated. You should use pd.Series.astype(float) or pd.to_numeric as described in other
answers.
This is available in 0.11. Forces conversion (or set's to nan)
This will work even when astype will fail; its als...
Send a file via HTTP POST with C#
... Thanks, I've used it with something simple and I't worked. Now, as you say, I do need to emulate a browser input file, somethig like this <intput type="file" name"userFile"/>.
– gabitoju
Jul 15 '09 at 13:51
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Get Base64 encode file-data from Input Form
...at, but it's here if you want to take a look; it's pretty neat.
What I do now:
The code for converting to string from a Uint8Array is pretty simple (where buf is a Uint8Array):
function uint8ToString(buf) {
var i, length, out = '';
for (i = 0, length = buf.length; i < length; i += 1) {...
Get the current time in C
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I know it's probably a bit late and you have likely figured it out by now, but you would use the strptime function in time.h to convert from char * to struct tm
– KingRadical
Nov 5 '13 at 1...