大约有 40,000 项符合查询结果（耗时：0.0276秒） [XML]
What does the “__block” keyword mean?
What exactly does the __block keyword in Objective-C mean? I know it allows you to modify variables within blocks, but I'd like to know...
...
How to rename with prefix/suffix?
...ly be short and simple for this. For example, to rename all *.jpg to prefix_*.jpg in the current directory:
for filename in *.jpg; do mv "$filename" "prefix_$filename"; done;
share
|
improve this ...
Hash function that produces short hashes?
...ike the accepted answer):
import base64
import hashlib
import uuid
unique_id = uuid.uuid4()
# unique_id = UUID('8da617a7-0bd6-4cce-ae49-5d31f2a5a35f')
hash = hashlib.sha1(str(unique_id).encode("UTF-8"))
# hash.hexdigest() = '882efb0f24a03938e5898aa6b69df2038a2c3f0e'
result = base64.b64encode(has...
ElasticSearch: Unassigned Shards, how to fix?
...enable shard allocation.
# v0.90.x and earlier
curl -XPUT 'localhost:9200/_settings' -d '{
"index.routing.allocation.disable_allocation": false
}'
# v1.0+
curl -XPUT 'localhost:9200/_cluster/settings' -d '{
"transient" : {
"cluster.routing.allocation.enable" : "all"
}
}'
Elas...
How to convert an image to base64 encoding?
...hould be:
$path = 'myfolder/myimage.png';
$type = pathinfo($path, PATHINFO_EXTENSION);
$data = file_get_contents($path);
$base64 = 'data:image/' . $type . ';base64,' . base64_encode($data);
share
|
...
How can I add new keys to a dictionary?
...gnoring the keys
Create a dictionary from two lists
data = dict(zip(list_with_keys, list_with_values))
New to Python 3.5
Creating a merged dictionary without modifying originals:
This uses a new featrue called dictionary unpacking.
data = {**data1, **data2, **data3}
New to Python 3.9...
detach all packages while working in R
...h()[pos]’. This can
be an unquoted name or a character string but _not_ a
character vector. If a number is supplied this is taken as
‘pos’.
So we need to repeatedly call detach() once per element of pkg. There are a couple of other arguments we need to specify to get thi...
How do I use vimdiff to resolve a git merge conflict?
...at I want on the terminal, e.g. something along:
--- ./src/dev/arm/RealView_BASE_15560.py 2019-12-27 13:46:41.967021591 +0000
+++ ./src/dev/arm/RealView_LOCAL_15560.py 2019-12-27 13:46:41.979021479 +0000
@@ -994,7 +994,7 @@
...
Rename multiple files by replacing a particular pattern in the filenames using a shell script [dupli
...a pattern. For example following command will prepend string MyVacation2011_ to all the files with jpg extension.
rename 's/^/MyVacation2011_/g' *.jpg
or
rename <pattern> <replacement> <file-list>
sha...
Truncating all tables in a Postgres database
.../pgSQL can do this. Here's the script:
CREATE OR REPLACE FUNCTION truncate_tables(username IN VARCHAR) RETURNS void AS $$
DECLARE
statements CURSOR FOR
SELECT tablename FROM pg_tables
WHERE tableowner = username AND schemaname = 'public';
BEGIN
FOR stmt IN statements LOOP
...