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Installing R with Homebrew
I'm trying to install R using Homebrew. I ran these commands which are recommended elsewhere on SO:
12 Answers
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Why 0 is true but false is 1 in the shell?
The above will output 1 , which is contradictory with all other programming languages I know.
10 Answers
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How do I filter ForeignKey choices in a Django ModelForm?
... can populate the validation data by making using the super(...).__init__ call in your overridden method. If you are making several of these queryset changes its a lot more elegant to package them by overriding the init method.
– michael
Aug 7 '09 at 4:53
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Shards and replicas in Elasticsearch
...e need to create an index.
When you create an index (an index is automatically created when you index the first document as well) you can define how many shards it will be composed of. If you don't specify a number it will have the default number of shards: 5 primaries. What does it mean?
It mean...
How can I specify working directory for popen
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Get last n lines of a file, similar to tail
... blocks.append(f.read(BLOCK_SIZE))
else:
# file too small, start from begining
f.seek(0,0)
# only read what was not read
blocks.append(f.read(block_end_byte))
lines_found = blocks[-1].count('\n')
lines_to_go -= lines_found
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How to delete all the rows in a table using Eloquent?
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The reason MyModel::all()->delete() doesn't work is because all() actually fires off the query and returns a collection of Eloquent objects.
You can make use of the truncate method, this works for Laravel 4 and 5:
MyModel::truncate();
Th...
How to darken a background using CSS?
....png);
}
Reference: linear-gradient() - CSS | MDN
UPDATE: Not all browsers support RGBa, so you should have a 'fallback color'. This color will be most likely be solid (fully opaque) ex:background:rgb(96, 96, 96). Refer to this blog for RGBa browser support.
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Perform .join on value in array of objects
...Array.prototype.map is what you're looking for if you want to code functionally.
[
{name: "Joe", age: 22},
{name: "Kevin", age: 24},
{name: "Peter", age: 21}
].map(function(elem){
return elem.name;
}).join(",");
In modern JavaScript:
[
{name: "Joe", age: 22},
{name: "Kevin", age: 2...
Do I need to disable NSLog before release Application?
... get debug messages. When you're ready to release a beta or final release, all those DLog lines automatically become empty and nothing gets emitted. This way there's no manual setting of variables or commenting of NSLogs required. Picking your build target takes care of it.
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