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Why does the default parameterless constructor go away when you create one with parameters
...ass, I most likely want to be able to instantiate that class. In order to allow that, the compiler must add a parameterless constructor, which will have no effect but to allow instantiation. This means that I don't have to include an empty constructor in my code just to make it work.
If I've defin...
JavaScript post request like a form submit
...y: post('/contact/', {name: 'Johnny Bravo', csrfmiddlewaretoken: $("#csrf_token").val()});
– Davidson Lima
Nov 22 '17 at 16:09
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Given two directory trees, how can I find out which files differ by content?
If I want find the differences between two directory trees, I usually just execute:
10 Answers
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How do you check in python whether a string contains only numbers?
....isdigit():
From the isdigit documentation:
str.isdigit()
Return True if all characters in the string are digits and there is at least one character, False otherwise. Digits include decimal characters and digits that need special handling, such as the compatibility superscript digits. This covers ...
How to raise a ValueError?
...trates how to raise a ValueError the way you want. By-the-way, I think find_last(), find_last_index(), or something simlar would be a more descriptive name for this function. Adding to the possible confusion is the fact that Python already has a container object method named __contains__() that does...
Get file size, image width and height before upload
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when the value of i is alerted in the callback function reader.onload it shows a random increment! e.g. for 4 files the value as alerted was 0 3 2 1 . Can any one explain that?
– freerunner
Mar 2 '14 at 11:16
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Concept of void pointer in C programming
...ligned at 4-byte boundary to be dereferenced).
For example, reading uint16_t from void*:
/* may receive wrong value if ptr is not 2-byte aligned */
uint16_t value = *(uint16_t*)ptr;
/* portable way of reading a little-endian value */
uint16_t value = *(uint8_t*)ptr
| ((*((uint8_t*)...
Using isKindOfClass with Swift
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Another approach using the new Swift 2 syntax is to use guard and nest it all in one conditional.
guard let touch = object.AnyObject() as? UITouch, let picker = touch.view as? UIPickerView else {
return //Do Nothing
}
//Do something with picker
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AngularJS - convert dates in controller
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All solutions here doesn't really bind the model to the input because you will have to change back the dateAsString to be saved as date in your object (in the controller after the form will be submitted).
If you don't need t...
binning data in python with scipy/numpy
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The Scipy (>=0.11) function scipy.stats.binned_statistic specifically addresses the above question.
For the same example as in the previous answers, the Scipy solution would be
import numpy as np
from scipy.stats import binned_statistic
data = np.random.rand(100)
bin_means = binned_stat...