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Does pandas iterrows have performance issues?
...ou use a function with a try-catch), they are good for a lot of use cases (string/regex stuff) where pandas methods do not have vectorized (in the truest sense of the word) implementations. Do you think it is worth mentioning LCs are a faster, lower overhead alternative to pandas apply and many pand...
Seeding the random number generator in Javascript
...lly, hash functions are very good at generating seeds for PRNGs from short strings. A good hash function will generate very different results even when two strings are similar. Here's an example based on MurmurHash3's mixing function:
function xmur3(str) {
for(var i = 0, h = 1779033703 ^ str.le...
How to access a mobile's camera from a web app?
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Both capture="camera" (String) and the older accept="image/*;capture=camera" have been replaced in 2012 with capture="capture" (Boolean) . The attribute is used to force capture instead of selecting from the library. See the spec and Correct Syntax...
return query based on date
....3 using Node v0.12.7 and v4.4.4 and used:
{ $gte: new Date(dateVar).toISOString() }
I'm passing in an ISODate (e.g. 2016-04-22T00:00:00Z) and this works for a .find() query with or without the toISOString function. But when using in an .aggregate() $match query it doesn't like the toISOString fu...
Read connection string from web.config
How can I read a connection string from a web.config file into a public class contained within a class library?
12 Answer...
Is there a limit on how much JSON can hold?
...the "default is 2097152 characters, which is equivalent to 4 MB of Unicode string data" for the property JavaScriptSerializer.MaxJsonLength mentioned in Amber's answer. (N.B. I have quoted from MSDN)
– dumbledad
Dec 12 '12 at 20:38
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Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
...w Integer[1];
arr[0] = "Hello, there!";
We just assigned a value of type String to an array of type Integer[]. For reasons which should be obvious, this is bad news. Java's type system actually allows this at compile time. The JVM will "helpfully" throw an ArrayStoreException at runtime. Scala...
What is a segmentation fault?
...as marked as read-only:
char *str = "Foo"; // Compiler marks the constant string as read-only
*str = 'b'; // Which means this is illegal and results in a segfault
Dangling pointer points to a thing that does not exist any more, like here:
char *p = NULL;
{
char c;
p = &c;
}
// Now p ...
How to check if a query string value is present via JavaScript?
How can I check if the query string contains a q= in it using JavaScript or jQuery?
10 Answers
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Objective-C: Extract filename from path string
When I have NSString with /Users/user/Projects/thefile.ext I want to extract thefile with Objective-C methods.
3 Answ...