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Setting a property by reflection with a string value
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You can use Convert.ChangeType() - It allows you to use runtime information on any IConvertible type to change representation formats. Not all conversions are possible, though, and you may need to write special case logic if you want to support conversions from t...
How to prevent ifelse() from turning Date objects into numeric objects
...irst this felt a little "hackish" to me. But now I just think of it as a small price to pay for the performance returns that I get from ifelse(). Plus it's still a lot more concise than a loop.
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What is a “callback” in C and how are they implemented?
...y're implemented using function pointers. Here's an example:
void populate_array(int *array, size_t arraySize, int (*getNextValue)(void))
{
for (size_t i=0; i<arraySize; i++)
array[i] = getNextValue();
}
int getNextRandomValue(void)
{
return rand();
}
int main(void)
{
int m...
Modular multiplicative inverse function in Python
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If you happen to be using sympy, then x, _, g = sympy.numbers.igcdex(a, m) does the trick.
– Lynn
Sep 16 '16 at 18:15
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How to initialize std::vector from C-style array?
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Don't forget that you can treat pointers as iterators:
w_.assign(w, w + len);
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Get keys from HashMap in Java
...HashMap contains more than one key. You can use keySet() to get the set of all keys.
team1.put("foo", 1);
team1.put("bar", 2);
will store 1 with key "foo" and 2 with key "bar". To iterate over all the keys:
for ( String key : team1.keySet() ) {
System.out.println( key );
}
will print "foo"...
Accessing an SQLite Database in Swift
...robably use one of the many SQLite wrappers, if you wanted to know how to call the SQLite library yourself, you would:
Configure your Swift project to handle SQLite C calls. If using Xcode 9 or later, you can simply do:
import SQLite3
Create/open database.
let fileURL = try! FileManager.default...
Get fully qualified class name of an object in Python
...lowing program
#! /usr/bin/env python
import foo
def fullname(o):
# o.__module__ + "." + o.__class__.__qualname__ is an example in
# this context of H.L. Mencken's "neat, plausible, and wrong."
# Python makes no guarantees as to whether the __module__ special
# attribute is defined, so we...
Back to previous page with header( “Location: ” ); in PHP
...this may not work with secure pages (HTTPS) and it's a pretty bad idea overall as the header can be hijacked, sending the user to some other destination. The header may not even be sent by the browser.
Ideally, you will want to either:
Append the return address to the request as a query variable ...
Sequelize.js: how to use migrations and sync
...rst migration"
In your case, the most reliable way is to do it almost manually. I would suggest to use sequelize-cli tool. The syntax is rather plain:
sequelize init
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sequelize model:create --name User --attributes first_name:string,last_name:string,bio:text
This will create both model AND mi...