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find vs find_by vs where
...is used as a helper when you're searching for information within a column, and it maps to such with naming conventions. For instance, if you have a column named name in your database, you'd use the following syntax:
Model.find_by(name: "Bob")
.where is more of a catch all that lets you use a bit...
Which parts of Real World Haskell are now obsolete or considered bad practice?
...rsion 3.0.x.x. 6.10.1 already used 4.0.0.0, which introduced many changes. And that's just the jump from 6.8 to 6.10. The current version of GHC is 7.10. Monads have been changed. There's currently a discussion to remove return from Monad, so the Monad instance in Real World Haskell will really be o...
What is the fastest way to get the value of π?
... fastest π I know of is the one with the digits hard coded. Looking at Pi and Pi[PDF], there are a lot of formulae.
Here is a method that converges quickly — about 14 digits per iteration. PiFast, the current fastest application, uses this formula with the FFT. I'll just write the formula, since...
Array Size (Length) in C#
...nt[,] b = new int[3, 5];)
b.Rank
will give the number of dimensions (2) and
b.GetLength(dimensionIndex)
will get the length of any given dimension (0-based indexing for the dimensions - so b.GetLength(0) is 3 and b.GetLength(1) is 5).
See System.Array documentation for more info.
As @Lucero ...
Context switches much slower in new linux kernels
...e intel_idle driver ignores the user's BIOS configuration for the C-states and dances to its own tune. In other words, even if you completely disable all C states in your PC's (or server's) BIOS, this driver will still force them on during periods of brief inactivity, which are almost always happeni...
fatal: early EOF fatal: index-pack failed
I have googled and found many solutions but none work for me.
31 Answers
31
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How can I export tables to Excel from a webpage [closed]
...s to Excel from a webpage. I want the export to contain all the formatting and colours.
14 Answers
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What is the difference between linear regression and logistic regression?
...ut as probabilities but it's a mistake because the output can be negative, and greater than 1 whereas probability can not. As regression might actually
produce probabilities that could be less than 0, or even bigger than
1, logistic regression was introduced.
Source: http://gerardnico.com/wiki/dat...
jQuery Tips and Tricks
...
Creating an HTML Element and keeping a reference
var newDiv = $("<div />");
newDiv.attr("id", "myNewDiv").appendTo("body");
/* Now whenever I want to append the new div I created,
I can just reference it from the "newDiv" variable */
...
How to spyOn a value property (rather than a method) with Jasmine
...me' is the name of that one defined in your class as get myGetterName() {} and the third param is the type get or set.
You can use the same assertions that you already use with the spies created with spyOn.
So you can for example:
const spy = spyOnProperty(myObj, 'myGetterName', 'get'); // to stu...