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How to search for “R” materials? [closed]
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http://rseek.org is a great search engine for R manuals, mailing lists, and various websites. It's a Google syndicated search app with specialized UI. I always use it.
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Is there a command to list SVN conflicts?
Does anyone know an SVN command to list current conflicts between the repo and the working copy?
9 Answers
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SQL to find the number of distinct values in a column
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You can use the DISTINCT keyword within the COUNT aggregate function:
SELECT COUNT(DISTINCT column_name) AS some_alias FROM table_name
This will count only the distinct values for that column.
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How to loop through a plain JavaScript object with the objects as members?
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for (var key in validation_messages) {
// skip loop if the property is from prototype
if (!validation_messages.hasOwnProperty(key)) continue;
var obj = validation_messages[key];
for (var prop in obj) {
// skip...
Why is “while ( !feof (file) )” always wrong?
I've seen people trying to read files like this in a lot of posts lately:
5 Answers
5
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Best/Most Comprehensive API for Stocks/Financial Data [closed]
What is the most recommended free/public API for accessing financial market stats and stock quotes (preferrably real-time quotes)? I'm not too picky about how it's exposed (SOAP, REST, some proprietary XML setup, etc.), as long as it's got some decent documentation.
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Where are the PostgreSQL logs on macOS?
I would like to take a look at the PostgreSQL log files to see what my app writes to them but I can't find them.
8 Answers
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What's an easy way to read random line from a file in Unix command line?
...here is also a utility called rl. In Debian it's in the randomize-lines package that does exactly what you want, though not available in all distros. On its home page it actually recommends the use of shuf instead (which didn't exist when it was created, I believe). shuf is part of the GNU coreuti...
What is mutex and semaphore in Java ? What is the main difference?
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EricEric
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Splitting a list into N parts of approximately equal length
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This code is broken due to rounding errors. Do not use it!!!
assert len(chunkIt([1,2,3], 10)) == 10 # fails
Here's one that could work:
def chunkIt(seq, num):
avg = len(seq) / float(num)
out = []
last = 0.0
while last...