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What is the relation between BLAS, LAPACK and ATLAS
...ovides an optimized implementation of a few of the LAPACK subroutines, and then optionally pulls in the rest of them from LAPACK itself to produce a complete LAPACK implementation in the built ATLAS lib files.
– Andrew Janke
Jan 24 '19 at 10:19
...
Difference between == and ===
... // false
(st as AnyObject) === (st as AnyObject) // false
but then you can also have fun as follows:
var st4 = st // "123"
st4 == st // true
st4 += "5" // "1235"
st4 == st // false, not quite a reference, copy on write semantics
...
How update the _id of one MongoDB Document?
...ou cannot update it. You'll have to save the document using a new _id, and then remove the old document.
// store the document in a variable
doc = db.clients.findOne({_id: ObjectId("4cc45467c55f4d2d2a000002")})
// set a new _id on the document
doc._id = ObjectId("4c8a331bda76c559ef000004")
// ins...
What is the exact problem with multiple inheritance?
... or whatever)
E.g. if you inherit from A and B, both having method foo(), then of course you don't want an arbitrary choice in your class C inheriting from both A and B.
You have to either redefine foo so it's clear what will be used if c.foo() is called or otherwise you have to rename one of the m...
Are Databases and Functional Programming at odds?
...siderations more effectively than any front end language." Oh really? Why, then, is it that SQL constraints still cannot do things like this?
– Robin Green
May 9 '12 at 19:46
...
Folder structure for a Node.js project
...s
│
└─ entities
├─ book.js
└─ author.js
We then add on the user and loan features:
user
├─ controllers
│ └─ userController.js
├─ entities
│ └─ user.js
└─ middleware
└─ authentication.js
loan
├─ controllers
│ ...
Validate decimal numbers in JavaScript - IsNumeric()
...a number fails, the expression will result in NaN. This numeric result is then compared to the original value you passed in. Since the left hand side is now numeric, type coercion is again used. Now that the input from both sides was coerced to the same type from the same original value, you woul...
How to get cumulative sum
...
A CTE version, just for fun:
;
WITH abcd
AS ( SELECT id
,SomeNumt
,SomeNumt AS MySum
FROM @t
WHERE id = 1
UNION ALL
SELECT t.id
...
How may I sort a list alphabetically using jQuery?
...
You do not need jQuery to do this...
function sortUnorderedList(ul, sortDescending) {
if(typeof ul == "string")
ul = document.getElementById(ul);
// Idiot-proof, remove if you want
if(!ul) {
alert("The UL object is null!");
return;
}
// G...
select * vs select column
...ob data is stored in separate Page-chunks, and the actual table row column then only gets a pointer...). But these exceptions are just that, exceptions, and generally do not apply except in special cases ( for special types of data, or certain optimizations for special circumstances)
Even in these ...