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Multiple “order by” in LINQ
...correct orderings if CategoryID is an int. For example, something with id=123, name=5times will appear after id=1234, name=something instead of before. It's also not inefficient to do string comparisons where int comparisons could occur.
– AaronLS
May 6 '13 a...
Is “IF” expensive?
...of for and while loops. Unconditional branches show up in infinite loops, function calls, function returns, break and continue statements, the infamous goto statement, and many more (these lists are far from exhaustive).
The branch target is another important issue. Most branches have a fixed bra...
How to document a method with parameter(s)?
...
123
Since docstrings are free-form, it really depends on what you use to parse code to generate AP...
Why aren't programs written in Assembly more often? [closed]
...has twice as many registers?
The converse of this question would be: What functionality do compilers provide?
I doubt you can/want to/should optimize your ASM better than gcc -O3 can.
share
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How do you remove a specific revision in the git history?
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123
Here is a way to remove non-interactively a specific <commit-id>, knowing only the <c...
Indent multiple lines quickly in vi
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123
A big selection would be:
gg=G
It is really fast, and everything gets indented ;-)
...
Checking if a double (or float) is NaN in C++
Is there an isnan() function?
21 Answers
21
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Is it possible to dynamically compile and execute C# code fragments?
...ce short example take from LukeH's blog, which uses some LINQ too just for fun.
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.CSharp;
using System.CodeDom.Compiler;
class Program
{
static void Main(string[] args)
{
var csc = new CSharpCodeProvid...
Why can't (or doesn't) the compiler optimize a predictable addition loop into a multiplication?
...lways point to MyArray any time that instruction executed, but it didn't. Fun.
– supercat
Apr 3 '13 at 16:51
then why...
filter for complete cases in data.frame using dplyr (case-wise deletion)
... passing it to the filter.
Another benchmark with more columns:
set.seed(123)
x <- sample(1e5,1e5*26, replace = TRUE)
x[sample(seq_along(x), 1e3)] <- NA
df <- as.data.frame(matrix(x, ncol = 26))
library(microbenchmark)
microbenchmark(
na.omit = {df %>% na.omit},
filter.anonymous = ...