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Removing duplicates from a list of lists
... much easier that it offers good returns on efforts. But sometimes (essentially for "tragically crucial bottlenecks" in deep inner loops of code that's pushing the boundaries of performance limits) one may need to go into much more detail, providing probability distributions, deciding which performa...
Null vs. False vs. 0 in PHP
...ers can spot/utilize the difference between Null and False and 0 and all the other good "nothing" entities.
What is the difference, specifically in PHP? Does it have something to do with === ?
...
ActiveRecord: size vs count
...l valid.
You'll adapt the function you use depending on your needs.
Basically:
if you already load all entries, say User.all, then you should use length to avoid another db query
if you haven't anything loaded, use count to make a count query on your db
if you don't want to bother with these con...
How to write logs in text file when using java.util.logging.Logger
I have a situation in which I want to write all logs created by me into a text file.
10 Answers
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CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清泛网 - 专注C/C++及内核技术
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...
CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清泛网 - 专注C/C++及内核技术
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...
iOS 7 status bar back to iOS 6 default style in iPhone app?
...clear background.
Status bar appearance is controlled along one of two mutually-exclusive basis paths: you can either set them programmatically in the traditional manner, or UIKit will update the appearance for you based on some new properties of UIViewController. The latter option is on by default....
Setting different color for each series in scatter plot on matplotlib
...
I don't know what you mean by 'manually'. You can choose a colourmap and make a colour array easily enough:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.cm as cm
x = np.arange(10)
ys = [i+x+(i*x)**2 for i in range(10)]
colors = cm.ra...
How do you serialize a model instance in Django?
...
You can easily use a list to wrap the required object and that's all what django serializers need to correctly serialize it, eg.:
from django.core import serializers
# assuming obj is a model instance
serialized_obj = serializers.serialize('json', [ obj, ])
...
What exactly are DLL files, and how do they work?
... files, ...) that an EXE, or other DLL uses.
Types of libraries:
On virtually all operating systems, there are 2 types of libraries. Static libraries and dynamic libraries. In windows the file extensions are as follows: Static libraries (.lib) and dynamic libraries (.dll). The main difference i...