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Extract first item of each sublist
I am wondering what is the best way to extract the first item of each sublist in a list of lists and append it to a new list. So if I have:
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mysqli or PDO - what are the pros and cons? [closed]
...nvincing somebody works better with a killer feature. So there it is:
A really nice thing with PDO is you can fetch the data, injecting it automatically in an object. If you don't want to use an ORM (cause it's a just a quick script) but you do like object mapping, it's REALLY cool :
class Student...
LINQ order by null column where order is ascending and nulls should be last
...nslated to LINQ method calls.
It turns out that
var products = from p in _context.Products
where p.ProductTypeId == 1
orderby p.LowestPrice.HasValue descending
orderby p.LowestPrice descending
select p;
will be translated by the compile...
Python Create unix timestamp five minutes in the future
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Now in Python >= 3.3 you can just call the timestamp() method to get the timestamp as a float.
import datetime
current_time = datetime.datetime.now(datetime.timezone.utc)
unix_timestamp = current_time.timestamp() # works if Python >= 3.3
unix_timestamp_pl...
Compiling Java 7 code via Maven
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Check the mvn script in your maven installation to see how it's building the command. Perhaps you or someone else has hard-coded a JAVA_HOME in there and forgotten about it.
share
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What's the difference between HEAD^ and HEAD~ in Git?
...f thumb
Use ~ most of the time — to go back a number of generations, usually what you want
Use ^ on merge commits — because they have two or more (immediate) parents
Mnemonics:
Tilde ~ is almost linear in appearance and wants to go backward in a straight line
Caret ^ suggests an interesting s...
Sorting object property by values
...ou like, thus achieving exactly what you set out to do. That would work in all the browsers I know of, but it would be dependent on an implementation quirk, and could break at any time. You should never make assumptions about the order of elements in a JavaScript object.
var objSorted = {}
sortable....
How do you kill a Thread in Java?
...ee this using Thread.currentThread.getThreadGroup().list(); it will prints all the threads its has and you will see multiple instances of your thread if you repeat your flow.
– AZ_
Jun 10 '11 at 14:08
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Read error response body in Java
...ere is to code like this:
HttpURLConnection httpConn = (HttpURLConnection)_urlConnection;
InputStream _is;
if (httpConn.getResponseCode() < HttpURLConnection.HTTP_BAD_REQUEST) {
_is = httpConn.getInputStream();
} else {
/* error from server */
_is = httpConn.getErrorStream();
}
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CSV new-line character seen in unquoted field error
...csv file itself, but this might work for you, give it a try, replace:
file_read = csv.reader(self.file)
with:
file_read = csv.reader(self.file, dialect=csv.excel_tab)
Or, open a file with universal newline mode and pass it to csv.reader, like:
reader = csv.reader(open(self.file, 'rU'), dialec...