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Delete a key from a MongoDB document using Mongoose
...rs. So you can do the action in question by this:
User.collection.update({_id: user._id}, {$unset: {field: 1 }});
Since version 2.0 you can do:
User.update({_id: user._id}, {$unset: {field: 1 }}, callback);
And since version 2.4, if you have an instance of a model already you can do:
doc.fiel...
How to find the Windows version from the PowerShell command line
...t is client or server Windows, nor the name of the version.
Use WMI's Win32_OperatingSystem class (always single instance), for example:
(Get-WmiObject -class Win32_OperatingSystem).Caption
will return something like
Microsoft® Windows Server® 2008 Standard
...
How do I get the row count of a pandas DataFrame?
...g",
setup=lambda n: pd.DataFrame(np.arange(n * 3).reshape(n, 3)),
n_range=[2**k for k in range(25)],
kernels=[
lambda data: data.shape[0],
lambda data: data[0].count(),
lambda data: len(data.index),
],
labels=["data.shape[0]", "data[0].count()", "len(data....
How can I parse a YAML file from a Linux shell script?
...han one level deep.
YAML looks like so:
KEY: value
ANOTHER_KEY: another_value
OH_MY_SO_MANY_KEYS: yet_another_value
LAST_KEY: last_value
Output like-a dis:
KEY="value"
ANOTHER_KEY="another_value"
OH_MY_SO_MANY_KEYS="yet_another_value"
LAST_KEY="last_value"
I ac...
How to dump a dict to a json file?
...
@Dan-ish Have you tried json.dump(sample, fp, sort_keys=False ) ? Assuming I understand what you mean.
– Chris Larson
Dec 26 '16 at 5:18
3
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Django self-referential foreign key
...ning the model property. If the property were being defined as part of the __init__() or another method, it would be, as self is always the first positional argument to any instance method of a Python class.
– Brandon
Nov 2 '16 at 12:58
...
How do I activate a virtualenv inside PyCharm's terminal?
... to get the full path to the current directory?
– bad_coder
Jun 22 at 2:38
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How to create NS_OPTIONS-style bitmask enumerations in Swift?
...le's documentation about interacting with C APIs, they describe the way NS_ENUM -marked C-style enumerations are imported as Swift enumerations. This makes sense, and since enumerations in Swift are readily provided as the enum value type it's easy to see how to create our own.
...
Does Javascript pass by reference? [duplicate]
...y value:
function replace(ref) {
ref = {}; // this code does _not_ affect the object passed
}
function update(ref) {
ref.key = 'newvalue'; // this code _does_ affect the _contents_ of the object
}
var a = { key: 'value' };
replace(a); // a still has its original value - it's un...
How to know/change current directory in Python shell?
...now how to change.
edit
Under Windows:
set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib
(taken from http://docs.python.org/using/windows.html)
edit 2
... and even better: use virtualenv and virtualenv_wrapper, this will allow you to create a development environment where you can add module paths ...