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Difference between Select and ConvertAll in C#
...INQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You should favor Select over ConvertAll as it works for any kind of list, but they do the sam...
How to Get the Title of a HTML Page Displayed in UIWebView?
...ww.google.com"];
//for any exceptions/errors
NSError *error;
//converts the url html to a string
NSString *htmlCode = [NSString stringWithContentsOfURL:currentURL encoding:NSASCIIStringEncoding error:&error];
So we have the HTML code, now how do we get the title? Well, in every...
How to get current timestamp in string format in Java? “yyyy.MM.dd.HH.mm.ss”
..., should only be used for transfer in and out of the database. Immediately convert to java.time types in Java 8 and later.
java.time.Instant
A java.sql.Timestamp maps to a java.time.Instant, a moment on the timeline in UTC. Notice the new conversion method toInstant added to the old class.
java.sql....
What is the best method of handling currency/money?
...e calculation.
If you insist on using integers, you will have to manually convert to and from BigDecimals everywhere, which will probably just become a pain.
As pointed out by mcl, to print the price, use:
number_to_currency(price, :unit => "€")
#=> €1,234.01
...
Does it make sense to use “as” instead of a cast even if there is no null check? [closed]
...ly, such a use case does not make sense for the To method here, as it only converts across the inheritance hierarchy, which for value types involves boxing anyway. Of course, the entire idea is more theoretical than serious.
– Mehrdad Afshari
Nov 28 '12 at 7:13...
Why does HTML think “chucknorris” is a color?
...
You can also use my random string to css color converter to get the color for a specific string. It's based on the 5 steps to calculate the string color by Jeremy Goodell.
– TimPietrusky
Mar 11 '13 at 16:45
...
Is Python interpreted, or compiled, or both?
...tion to native machine code. A compiler is, more generally, a program that converts a program in one programming language into a program in another programming language (arguably, you can even have a compiler with the same input and output language if significant transformations are applied). And JI...
Breaking loop when “warnings()” appear in R
... loop. Nicely, R will also report to you that these particular errors were converted from warnings.
j <- function() {
for (i in 1:3) {
cat(i, "\n")
as.numeric(c("1", "NA"))
}}
# warn = 0 (default) -- warnings as warnings!
j()
# 1
# 2
# 3
# Warning messages:
# 1: NAs intro...
What does .SD stand for in data.table in R
...
Edit:
Given how well-received this answer was, I've converted it into a package vignette now available here
Given how often this comes up, I think this warrants a bit more exposition, beyond the helpful answer given by Josh O'Brien above.
In addition to the Subset of the D...
What is the purpose of a plus symbol before a variable?
...ein from the MDN link in the answer: "Although unary negation (-) also can convert non-numbers, unary plus is the fastest and preferred way of converting something into a number, because it does not perform any other operations on the number." (just for an "official" answer)
– ...