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Initialize class fields in constructor or at declaration?
...as we don't comment each foreach loop with "this repeats the following for all items in the list", we don't need to constantly restate C#'s default values. We also don't need to pretend that C# has uninitialized semantics. Since the absence of a value has a clear meaning, it's fine to leave it out. ...
xpath find if node exists
Using a xpath query how do you find if a node (tag) exists at all?
6 Answers
6
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What is an intuitive explanation of the Expectation Maximization technique? [closed]
... around 7 (and we could find the exact means if we wanted).
This is, generally speaking, known as maximum likelihood estimation. Given some data, we compute the value of a parameter (or parameters) that best explains that data.
Now imagine that we cannot see which value was sampled from which grou...
Preserve line endings
... run sed to do some substitution on windows and I noticed that it automatically converts line endings to Unix (\n). Is there an option to tell sed to use Windows line endings (\r\n) or even better to preserve the line endings from the file?
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RegEx to extract all matches from string using RegExp.exec
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Continue calling re.exec(s) in a loop to obtain all the matches:
var re = /\s*([^[:]+):\"([^"]+)"/g;
var s = '[description:"aoeu" uuid:"123sth"]';
var m;
do {
m = re.exec(s);
if (m) {
console.log(m[1], m[2]);
}
} ...
DISTINCT for only one column
... needs a WHERE condition. I'm thinking the row numbers will be assigned to all rows in the table. This syntax is just a little beyond me. Any chance of an update that would guarantee one row with a particular email that meets the WHERE condition?
– Jonathan Wood
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WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
...If you use the set transaction isolation level statement, it will apply to all the tables in the connection, so if you only want a nolock on one or two tables use that; otherwise use the other.
Both will give you dirty reads. If you are okay with that, then use them. If you can't have dirty reads,...
How to redirect stderr and stdout to different files in the same line in script?
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Great answer! I really like your explanation of how 1> can be written as >
– user784637
Oct 26 '11 at 13:25
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Credit card expiration dates - Inclusive or exclusive?
...calculate the end of the month like you'd want for a credit card.
Additionally, this page has everything you ever wanted to know about credit cards.
This is assumed to be a typo and that it should read "..., after the first day of the next month; ..."
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sed command with -i option (in-place editing) works fine on Ubuntu but not Mac [duplicate]
... That's simpler than trying to work out which variant of sed you have installed or other gizmos I've seen suggested. I hope you keep the file under version control (or otherwise backed up) so that you can recover if there's a bug in your sed script. Of course, the .bak file gives you that protect...