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C++ include and import difference
...sed with .NET / CLI stuff.
Import in gcc:
The import in gcc is different from the import in VC++. It is a simple way to include a header at most once only. (In VC++ and GCC you can do this via #pragma once as well)
The #import directive was officially undeprecated by the gcc team in version 3.4 ...
How to drop rows of Pandas DataFrame whose value in a certain column is NaN
...e missing data, including dropna(), is built into pandas explicitly. Aside from potentially improved performance over doing it manually, these functions also come with a variety of options which may be useful.
In [24]: df = pd.DataFrame(np.random.randn(10,3))
In [25]: df.iloc[::2,0] = np.nan; df....
(-2147483648> 0) returns true in C++?
...t can: 2147483648 has unsigned int ???? type.
In the second you force int from the unsigned.
const bool i= (-2147483648 > 0) ; // --> true
warning C4146: unary minus operator applied to unsigned type, result still unsigned
Here are related "curiosities":
const bool b= (-21474836...
How can I reverse a NSArray in Objective-C?
...rse any NSMutableArray in place:
/* Algorithm: swap the object N elements from the top with the object N
* elements from the bottom. Integer division will wrap down, leaving
* the middle element untouched if count is odd.
*/
for(int i = 0; i < [array count] / 2; i++) {
int j = [array co...
The most accurate way to check JS object's type?
...
|| (cache[key] = key.slice(8, -1).toLowerCase()); // get XXXX from [object XXXX], and cache it
};
}(this));
use as:
type(function(){}); // -> "function"
type([1, 2, 3]); // -> "array"
type(new Date()); // -> "date"
type({}); // -> "object"
...
are there dictionaries in javascript like python?
...
If the value comes from the user, then care needs to be taken to use Object.hasOwnProperty.call(dictionary, key) (otherwise the user can enter a value of valueOf and dictionary['valueOf'] returns the Object.valueOf() function belonging to the O...
Are there any SHA-256 javascript implementations that are generally considered trustworthy?
...gBuffer);
// convert ArrayBuffer to Array
const hashArray = Array.from(new Uint8Array(hashBuffer));
// convert bytes to hex string
const hashHex = hashArray.map(b => ('00' + b.toString(16)).slice(-2)).join('');
return hashHex;
}
Note that crypto.subtle in...
Disable Interpolation when Scaling a
...
I’m (from the present future!) on Chrome 78. I’m seeing “image-rendering: pixelated;” working. It looks like this was added in 2015 to Chrome 41: developers.google.com/web/updates/2015/01/pixelated
– Mr...
Start an Activity with a parameter
... You may want to make sure b != null before you start grabbing from it
– Andrew
Oct 12 '10 at 15:03
How ca...
wildcard ssl on sub-subdomain [closed]
...for *.example.net will match sub.example.net but not sub.sub.example.net.
From RFC 2818:
Matching is performed using the matching rules specified by
RFC2459. If more than one identity of a given type is present in
the certificate (e.g., more than one dNSName name, a match in any one
...