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“Large data” work flows using pandas
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I routinely use tens of gigabytes of data in just this fashion
e.g. I have tables on disk that I read via queries, create data and append back.
It's worth reading the docs and late in this thread for several suggestions for how to store your data.
Det...
Is recursion a feature in and of itself?
... yet, that was wrong.
Reading between the lines, one possibility is that by using recursion, you avoided ever using a feature that was supposed to be a learning outcome for his course. For example, maybe you didn't use iteration at all, or maybe you only used for loops instead of using both for an...
http HEAD vs GET performance
... or is slow to retrieve at the server, you might not see a measurable gain by using HEAD instead of GET. It could be that retrieving the meta data is not any faster than retrieving the entire resource.
You could implement both options and benchmark them to see which is faster, but rather than micro...
Django ManyToMany filter()
... User.objects.filter(zones__in=[<id1>])
# filtering on a few zones, by id
users_in_zones = User.objects.filter(zones__in=[<id1>, <id2>, <id3>])
# and by zone object (object gets converted to pk under the covers)
users_in_zones = User.objects.filter(zones__in=[zone1, zone2, z...
Setting Short Value Java
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In Java, integer literals are of type int by default. For some other types, you may suffix the literal with a case-insensitive letter like L, D, F to specify a long, double, or float, respectively. Note it is common practice to use uppercase letters for better readab...
Mipmap drawables for icons
...ity. For example on an hdpi tablet the launcher might load the xhdpi icon. By placing your launcher icon in the mipmap-xhdpi directory, it will not be stripped the way a drawable-xhdpi directory is when building an APK for hdpi devices. If you're building a single APK for all devices, then this does...
What is the difference between encrypting and signing in asymmetric encryption?
... your public key itself, which you have earlier generated for free, signed by an authority which might or might not charge you money for that.
– Quassnoi
Jul 26 '19 at 10:45
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Java default constructor
...class constructor with no arguments". Uninitialised fields are initialised by other mechanisms also described in this reference. +1 to OrangeDog for providing a good reference.
– Superole
Jan 28 '14 at 8:38
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UIPopovercontroller dealloc reached while popover is still visible
...en you don't need to keep a reference to the popover because it is managed by the presentation controller.
Code example (works both on iPhone and iPad):
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = UIImagePickerControllerSour...
Why does PHP consider 0 to be equal to a string?
...e', or 'E' and the numeric value fits into integer type limits (as defined by PHP_INT_MAX), the string will be evaluated as an integer. In all other cases it will be evaluated as a float.
In this case the string is 'e' and thus it will be evaluated as a float:
The value is given by the initial...