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Creating functions in a loop
...cated way which involved using a closure as a "function factory":
def make_f(i):
def f():
return i
return f
and in your loop use f = make_f(i) instead of the def statement.
share
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Filter rows which contain a certain string
...n easily extend to more than one column.
Below also a solution with filter_all in order to find the string in any column,
using diamonds as example, looking for the string "V"
library(tidyverse)
String in only one column
# for only one column... extendable to more than one creating a column list in...
Get Unix Epoch Time in Swift
...alSince1970)
let preciseMilliseconds = Int(Date().timeIntervalSince1970 * 1_000)
let preciseMicroseconds = Int(Date().timeIntervalSince1970 * 1_000_000) // most likely precise
Unfortunately, however, in the year 2038, 32-bit numbers won't be usable for the Unix timestamp and they'll have to be 64-...
How often does python flush to a file?
...t size.
A negative buffering means to use the system default, which is usually line buffered for tty devices and fully buffered for other files.
If omitted, the system default is used.
code:
bufsize = 0
f = open('file.txt', 'w', buffering=bufsize)
...
Java 8: performance of Streams vs Collections
I'm new to Java 8. I still don't know the API in depth, but I've made a small informal benchmark to compare the performance of the new Streams API vs the good old Collections.
...
.rar, .zip files MIME Type
...
actually there's another MIME TYPE for zip, and that's: application/x-zip-compressed
– Kiyarash
Oct 6 '14 at 19:21
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MySQL - length() vs char_length()
...() returns the length of the string measured in characters.
This is especially relevant for Unicode, in which most characters are encoded in two bytes. Or UTF-8, where the number of bytes varies. For example:
select length(_utf8 '€'), char_length(_utf8 '€')
--> 3, 1
As you can see the E...
How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
What is the difference between mocking and spying when using Mockito?
...
The answer is in the documentation:
Real partial mocks (Since 1.8.0)
Finally, after many internal debates & discussions on the mailing list, partial mock support was added to Mockito. Previously we considered partial mocks as code smells. However, we found a legitimate use case for partial mo...
how to File.listFiles in alphabetical order?
... File is a comparable class, which by default sorts pathnames lexicographically. If you want to sort them differently, you can define your own comparator.
If you prefer using Streams:
A more modern approach is the following. To print the names of all files in a given directory, in alphabetical or...