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Storing time-series data, relational or non?
...n is never a Key (duplicate rows, which are prohibited in a Relational database, must be prevented by other means).
The Id column requires an additional Index, which obviously impedes the speed of INSERT/DELETE, and adds to the disk space used.
You can get rid of it. Please.
Elevation
Now ...
How do I safely pass objects, especially STL objects, to and from a DLL?
...L, then examine the produced .def file (if one is produced; this will vary based on your project options) or use a tool like Dependency Walker to find the mangled name. Then, you'll need to write your own .def file, defining an unmangled alias to the mangled function. As an example, let's use the Ge...
Why does using an Underscore character in a LIKE filter give me all the results?
...ess supports like operator. My solution will work in most, if not all, databases.
– Rachcha
Oct 25 '13 at 13:51
2
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What is href=“#” and why is it used?
...n annoying jump to the top of the page, but in the case of sites using <base>, <a href="#"> is handled as <a href="[base href]/#">, resulting in an unexpected navigation. If any logable errors are being generated, you won't see them in the latter case unless you enable persistent ...
How to create a UIView bounce animation?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Make Bootstrap Popover Appear/Disappear on Hover instead of Click
...alization option:
$("#popover").popover({ trigger: "hover" });
Here's a DEMO.
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6个变态的C语言Hello World程序 - 创意 - 清泛网 - 专注C/C++及内核技术
...ne ___ _(0x6F)_(0x2C)_(0x20)_(0x77)_(0x6F)
#define ____ _(0x72)_(0x6C)_(0x64)_(0x21)
#define _____ __ ___ ____ _________
#include<stdio.h>
_____
hello2.c
#include<stdio.h>
main(){
int x=0,y[14],*z=&y;*(z++)=0x48;*(z++)=y[x++]+0x1D;
*(z++)=y[x++]+0x07;*(z++)=y[x++]+0x00;*(...
How do I get the row count of a pandas DataFrame?
...eturn non-NaN counts for each column:
df.count()
A 5
B 3
dtype: int64
For Series, use Series.count to similar effect:
s.count()
# 3
Group-wise Row Count: GroupBy.size
For DataFrames, use DataFrameGroupBy.size to count the number of rows per group.
df.groupby('A').size()
A
a 2
b ...
Benchmarking (python vs. c++ using BLAS) and (numpy)
...
CPU: 2 x 16 Intel(R) Xeon(R) E2560 Sandy Bridge @ 2.00GHz (16 Cores)
RAM: 64 GB
Ivy (MKL, OpenBLAS, ATLAS):
CPU: 2 x 20 Intel(R) Xeon(R) E2680 V2 Ivy Bridge @ 2.80GHz (20 Cores, with HT = 40 Cores)
RAM: 256 GB
Software
The software stack is for both nodes the sam. Instead of GotoBLAS2, OpenB...
How do you get centered content using Twitter Bootstrap?
...ol-*offset-* to center grid columns
see this answer to center the navbar
Demo Bootstrap 3 Horizontal Centering
Bootstrap 4
text-center is still used for display:inline elements
mx-auto replaces center-block to center display:block elements
offset-* or mx-auto can be used to center grid columns
...