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How to select a single field for all documents in a MongoDB collection?
...uery. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example from the folks at Mongo, the returned documents will contain only the fields of item, qty, and _id.
Thus...
How to find the JVM version from a program?
...version "12" "1.8.0_201" "1.5.0_22" Java Runtime Environment version, which may be interpreted as a Runtime.Version
java.version.date "2019-03-19" ...
No generic implementation of OrderedDictionary?
... private KeyedCollection2<TKey, KeyValuePair<TKey, TValue>> _keyedCollection;
/// <summary>
/// Gets or sets the value associated with the specified key.
/// </summary>
/// <param name="key">The key associated with the value to get or...
How to deal with SettingWithCopyWarning in Pandas?
...H5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] = new_val
However, this doesn't fit your usage, which is equivalent to:
df = df[df['A'] > 2]
df['B'] = ...
Stop pip from failing on single package when installing with requirements.txt
...optional dependencies:
#!/bin/sh
while read dependency; do
dependency_stripped="$(echo "${dependency}" | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//')"
# Skip comments
if [[ $dependency_stripped == \#* ]]; then
continue
# Skip blank lines
elif [ -z "$dependency_str...
How to decorate a class?
...r specific scenario, YMMV :-)
What you're thinking of is a metaclass. The __new__ function in a metaclass is passed the full proposed definition of the class, which it can then rewrite before the class is created. You can, at that time, sub out the constructor for a new one.
Example:
def substitu...
How to modify a global variable within a function in bash?
...mysecondfunc() {
echo "Hello"
return 4
}
var="$(mysecondfunc)"
num_var=$?
echo "$var - num is $num_var"
Gives:
Hello - num is 4
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Python Logging (function name, file name, line number) using a single file
...wise it would
# be this function!!!
func = inspect.currentframe().f_back.f_code
# Dump the message + the name of this function to the log.
logging.debug("%s: %s in %s:%i" % (
message,
func.co_name,
func.co_filename,
func.co_firstlineno
))
This...
ImportError in importing from sklearn: cannot import name check_build
...the kernel's socket connection. Fixed by renaming the file multiprocessing_.py (leading underscore did not work).
– pylang
Jan 11 '19 at 2:52
...
How to get a reference to a module inside the module itself?
...
import sys
current_module = sys.modules[__name__]
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