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Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...' the matrix.
#'
#' @param data data.frame: input data
#' @param rowtitle string: row-dimension; name of the column in data, which distinct values should be used as row names in the output matrix
#' @param coltitle string: col-dimension; name of the column in data, which distinct values should be u...
Deleting all files in a directory with Python
... list of file names which end it '.bak'. The elements of the list are just strings.
Then you could use os.unlink to remove the files. (PS. os.unlink and os.remove are synonyms for the same function.)
#!/usr/bin/env python
import glob
import os
directory='/path/to/dir'
os.chdir(directory)
files=glo...
Repair all tables in one go
...SE.repair_all()
BEGIN
DECLARE endloop INT DEFAULT 0;
DECLARE tableName char(100);
DECLARE rCursor CURSOR FOR SELECT `TABLE_NAME` FROM `information_schema`.`TABLES` WHERE `TABLE_SCHEMA`=DATABASE();
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET endloop=1;
OPEN rCursor;
FETCH rCursor I...
How can I use different certificates on specific connections?
...eArrayInputStream derInputStream = new ByteArrayInputStream(app.certificateString.getBytes());
CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
X509Certificate cert = (X509Certificate) certificateFactory.generateCertificate(derInputStream);
String alias = "alias";//ce...
Difference between single and double square brackets in Bash
...nsion.
expr a \< b > /dev/null: POSIX equivalent², see: How to test strings for lexicographic less than or equal in Bash?
&& and ||
[[ a = a && b = b ]]: true, logical and
[ a = a && b = b ]: syntax error, && parsed as an AND command separator cmd1 &&...
Collections.emptyMap() vs new HashMap()
...e this, and does not allow null references:
public ResultSet executeQuery(String query, Map<String, Object> queryParameters);
If you have a query that doesn't take any parameters, it's certainly a bit wasteful to create a HashMap, which involves allocating an array, when you could just pass...
Is it possible for a computer to “learn” a regular expression by user-provided examples?
...
Yes, it's certainly "possible"; Here's the pseudo-code:
string MakeRegexFromExamples(<listOfPosExamples>, <listOfNegExamples>)
{
if HasIntersection(<listOfPosExamples>, <listOfNegExamples>)
return <IntersectionError>
string regex = "";
...
The entitlements specified…profile. (0xE8008016). Error iOS 4.2
... run the HealthKit "fit" app for iOS8 - there was an additional identifier string in the entitlements file. Removing it allowed the project to run after following other steps mentioned in this thread
– Alex Stone
Jul 17 '14 at 18:38
...
How to configure logging to syslog in Python?
...
I add a little extra comment just in case it helps anyone because I found this exchange useful but needed this little extra bit of info to get it all working.
To log to a specific facility using SysLogHandler you need to specify the facili...
How to get a float result by dividing two integer values using T-SQL?
... answered Jul 30 '12 at 12:05
RichardRichard
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