大约有 3,000 项符合查询结果（耗时：0.0174秒） [XML]
Split delimited strings in a column and insert as new rows [duplicate]
...p1[!temp1$V == "", c("Ind", "V")]
# Ind V
# 1.1 1 a
# 2.1 2 a
# 3.1 3 b
# 4.1 4 e
# 1.2 1 b
# 2.2 2 c
# 3.2 3 d
# 4.2 4 f
# 1.3 1 c
Another fairly direct alternative is:
stack(
setNames(
sapply(strsplit(mydf$V2, ","),
function(x) gsub("^\\s|\\s$",...
Path to Powershell.exe (v 2.0)
...
I believe it's in C:\Windows\System32\WindowsPowershell\v1.0\. In order to confuse the innocent, MS kept it in a directory labeled "v1.0". Running this on Windows 7 and checking the version number via $Host.Version (Determine installed PowerShell version) shows it's 2.0.
Another o...
How to set HTTP headers (for cache-control)?
...-cache, must-revalidate"); //HTTP 1.1
header("Pragma: no-cache"); //HTTP 1.0
header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past
//or, if you DO want a file to cache, use:
header("Cache-Control: max-age=2592000"); //30days (60sec * 60min * 24hours * 30days)
?>
Note t...
How to exclude a module from a Maven reactor build?
...
I had moved from 3.1 to 3.2.1 without any issues. But to be honest, you would have to do a build to figure it out.
– Yogesh_D
Aug 14 '14 at 6:14
...
Which is faster in Python: x**.5 or math.sqrt(x)?
...(x) is always faster than x**.5 on another machine (Ubuntu, Python 2.6 and 3.1):
$ python -mtimeit -s"from math import sqrt; x = 123" "x**.5"
10000000 loops, best of 3: 0.173 usec per loop
$ python -mtimeit -s"from math import sqrt; x = 123" "sqrt(x)"
10000000 loops, best of 3: 0.115 usec per loop
...
1030 Got error 28 from storage engine
...y Mounted on
/dev/vdisk 13G 13G 46M 100% /
devfs 1.0k 1.0k 0B 100% /dev
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Change IPython/Jupyter notebook working directory
... Notice that this solution must be slightly changed with Ipython 3.1 as --pylab is not supported any longer. instead of ipython notebook "--pylab inline" write "ipython notebook"
– tagoma
Apr 5 '15 at 13:25
...
Get Folder Size from Windows Command Line
...\dotnet
140,67 C:\my\Tools\vscode
97,33 C:\my\Tools\apache-jmeter-3.1
54,39 C:\my\Tools\mongoadmin
47,89 C:\my\Tools\Python27
35,22 C:\my\Tools\robomongo
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How do you convert a byte array to a hexadecimal string, and vice versa?
...sing string.Concat, requires .NET 4.0) (via Will Dean)
Text: 752,078.70 (1.0X faster)
Sentence: 18.28 (2.2X faster)
{StringBuilder}.AppendFormat (using foreach) (via Tomalak)
Text: 672,115.77 (1.1X faster)
Sentence: 36.82 (1.1X faster)
{StringBuilder}.AppendFormat (using {IEnumerable}.Aggregat...
How to calculate age (in years) based on Date of Birth and getDate()
... @Now='1991-05-04', @Dob='1980-05-05' --results in 10.997260273973
SELECT 1.0* DateDiff(yy,@Dob,@Now)
+CASE
WHEN @Now >= DATEFROMPARTS(DATEPART(yyyy,@Now),DATEPART(m,@Dob),DATEPART(d,@Dob)) THEN --birthday has happened for the @now year, so add some portion onto the year differen...