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Make column not nullable in a Laravel migration
...aylor Otwell (creator of Laravel) said 6 days ago (2014-05-09): "I still stand by my statement that if anyone can successfully and cleanly do it I will merge it." github.com/laravel/framework/issues/895#issuecomment-42709756
– Ryan
May 15 '14 at 21:30
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Can dplyr package be used for conditional mutating?
... TRUE ~ NA_real_))
Added - arithmetic/na_if If the values are numeric and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using...
In Matlab, when is it optimal to use bsxfun?
...ng
Using bsxfun, like using accumarray, makes me feel good about my understanding of Matlab.
bsxfun will replicate the input arrays along their "singleton dimensions", i.e. the dimensions along which the size of the array is 1, so that they match the size of the corresponding dimension of the othe...
What does enumerable mean?
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An enumerable property is one that can be included in and visited during for..in loops (or a similar iteration of properties, like Object.keys()).
If a property isn't identified as enumerable, the loop will ignore that it's within the object.
var obj = { key: 'val' };
console...
What is NODE_ENV and how to use it in Express?
...ode application is run, it can check the value of the environment variable and do different things based on the value. NODE_ENV specifically is used (by convention) to state whether a particular environment is a production or a development environment. A common use-case is running additional debuggi...
Drawable image on a canvas
...w(canvas);
This will work with all kinds of drawables, not only bitmaps. And it also means that you can re-use that same drawable again if only the size changes.
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Ruby on Rails. How do I use the Active Record .build method in a :belongs to relationship?
...cts of the
collection type that have been
instantiated with attributes and
linked to this object through a
foreign key, but have not yet been
saved. Note: This only works if an
associated object already exists, not
if it‘s nil!
The answer to building in the opposite direction is a ...
How to compare dates in datetime fields in Postgresql?
...3 12:20:00). This column has the value as timestamp for all rows currently and have the same date part(2013-05-03) but difference in time part.
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Is it possible to animate scrollTop with jQuery?
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Why do you need both html and body? There is some insight here: stackoverflow.com/questions/2123690/…, but it is not a complete answer.
– Haralan Dobrev
Dec 13 '13 at 15:22
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Multiple file extensions in OpenFileDialog
... ?
I have Filter = "BMP|*.bmp|GIF|*.gif|JPG|*.jpg|PNG|*.png|TIFF|*.tiff"
and I want to create groups so JPG are *.jpg and *.jpeg, TIFF are *.tif and *.tiff and also 'All graphic types'? How can I do that?
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