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No appenders could be found for logger(log4j)?
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Warning messages are not appearing now but still the logs are not written at desired location
– Arpan Saini
Mar 3 '17 at 9:06
add a com...
How do I add 1 day to an NSDate?
...= [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
// now build a NSDate object for the next day
NSDateComponents *offsetComponents = [[NSDateComponents alloc] init];
[offsetComponents setDay:1];
NSDate *nextDate = [gregorian dateByAddingComponents:offsetComponents toDate: [N...
What's the difference between git reflog and log?
...ith some of your commit code) and delete the branches rm .git/refs/heads/*
Now git log --oneline will show only HEAD and its commits ancestors.
git reflog on the other hand is using direct log that is created inside .git/logs
Experiment: rm -rf .git/logs and git reflog is empty.
Anyway, even if you ...
What are the disadvantages of using persistent connection in PDO
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I know a big website that has been using persistent connections for nearly a decade now. The trick is using a layer above the DB extension, and having it remember the things that need to be cleaned up by using register_shutdown_...
What is PostgreSQL explain telling me exactly?
...but let's look at one clear example. Here's the same query from before but now containing an ORDER BY clause:
EXPLAIN SELECT * FROM post ORDER BY body LIMIT 50;
Limit (cost=23283.24..23283.37 rows=50 width=422)
-> Sort (cost=23283.24..23859.27 rows=230412 width=422)
Sort Key: body
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Creating an empty list in Python
...wrong-headed.
Readability is very subjective. I prefer [], but some very knowledgable people, like Alex Martelli, prefer list() because it is pronounceable.
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What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and be
...usability, and low runtime/compile time overhead. Eigen looks much better now than it did at that point, so I can't judge between them. However, I've been very happy with GMTL for our uses.
– Reed Copsey
Sep 9 '09 at 18:05
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iOS Image Orientation has Strange Behavior
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The first exif link is broken now, and the second has been updated to exif.regex.info/exif.cgi I tried to edit the answer but @cj-dennis rejected it for some reason.
– Ryan
Apr 12 '18 at 5:19
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java.lang.NoClassDefFoundError: org/hamcrest/SelfDescribing
...th my Lab/version of Eclipse. I had to remove it and add 4 and all is good now. Thanks a lot.
– Tony
Jul 19 '14 at 14:19
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What is the difference between “ is None ” and “ ==None ”
...mparison is implemented elementwise:
import numpy as np
a = np.zeros(3) # now a is array([0., 0., 0.])
a == None #compares elementwise, outputs array([False, False, False]), i.e. not boolean!!!
a is None #compares object to object, outputs False
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