大约有 6,000 项符合查询结果（耗时：0.0233秒） [XML]
Test if characters are in a string
...# Correct
> grepl("1+2", "1+2", fixed=TRUE)
[1] TRUE
> grepl("1+2", "123+456", fixed=TRUE)
[1] FALSE
# Incorrect
> grepl("1+2", "1+2")
[1] FALSE
> grepl("1+2", "123+456")
[1] TRUE
Interpretation
grep is named after the linux executable, which is itself an acronym of "Global Regular...
Regex Email validation
...ht, fail to catch at least two invalid formats: "Abc.@example.com" , "Abc..123@example.com"
– sean717
Aug 22 '12 at 5:22
...
Scheduling recurring task in Android
...k stackoverflow.com/questions/27872016/…
– dowjones123
Jan 10 '15 at 2:07
For simple things - like checking state ev...
Deleting all files in a directory with Python
...
Via os.listdir and os.remove:
import os
filelist = [ f for f in os.listdir(mydir) if f.endswith(".bak") ]
for f in filelist:
os.remove(os.path.join(mydir, f))
Or via glob.glob:
import glob, os, os.path
filelist = glob.g...
Calculating a directory's size using Python?
...
This walks all sub-directories; summing file sizes:
import os
def get_size(start_path = '.'):
total_size = 0
for dirpath, dirnames, filenames in os.walk(start_path):
for f in filenames:
fp = os.path.join(dirpath, f)
# skip if it is symbolic li...
Build an ASCII chart of the most commonly used words in a given text [closed]
...
123
votes
LabVIEW 51 nodes, 5 structures, 10 diagrams
Teaching the elephant to tap-d...
How do I programmatically determine operating system in Java?
I would like to determine the operating system of the host that my Java program is running programmatically (for example: I would like to be able to load different properties based on whether I am on a Windows or Unix platform). What is the safest way to do this with 100% reliability?
...
Open file in a relative location in Python
Suppose python code is executed in not known by prior windows directory say 'main' , and wherever code is installed when it runs it needs to access to directory 'main/2091/data.txt' .
...
How do I get the path and name of the file that is currently executing?
...
p1.py:
execfile("p2.py")
p2.py:
import inspect, os
print (inspect.getfile(inspect.currentframe()) # script filename (usually with path)
print (os.path.dirname(os.path.abspath(inspect.getfile(inspect.currentframe())))) # script directory
...
How do I compare version numbers in Python?
...3.a4"), version.Version)
True
>>> isinstance(version.parse("1.3.xy123"), version.LegacyVersion)
True
>>> version.Version("1.3.xy123")
Traceback (most recent call last):
...
packaging.version.InvalidVersion: Invalid version: '1.3.xy123'
packaging.version.parse is a third-party uti...