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python plot normal distribution
...ot as plt
import numpy as np
import scipy.stats as stats
import math
mu = 0
variance = 1
sigma = math.sqrt(variance)
x = np.linspace(mu - 3*sigma, mu + 3*sigma, 100)
plt.plot(x, stats.norm.pdf(x, mu, sigma))
plt.show()
s...
Gem::LoadError for mysql2 gem, but it's already in Gemfile
... with rails 4.1.5) try using this version of mysql2:
gem 'mysql2', '~> 0.3.18'
Apparently mysql2 isn't still compatible with newer version of rails because rails 4.2.4 is pretty new as the time of answering this question by me 8 September 2015 so use the above line in your Gem file and run:
...
[] and {} vs list() and dict(), which is better?
...s/dicts:
>>> from timeit import timeit
>>> timeit("[]")
0.040084982867934334
>>> timeit("list()")
0.17704233359267718
>>> timeit("{}")
0.033620194745424214
>>> timeit("dict()")
0.1821558326547077
and for non-empty:
>>> timeit("[1,2,3]")
0.243...
How to initialize all members of an array to the same value?
...
Unless that value is 0 (in which case you can omit some part of the initializer
and the corresponding elements will be initialized to 0), there's no easy way.
Don't overlook the obvious solution, though:
int myArray[10] = { 5, 5, 5, 5, 5, 5, 5,...
How can I split a string into segments of n characters?
...
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edited Jun 30 '16 at 3:03
Ruslan López
3,91811 gold badge1818 silver badges3131 bronze badges
...
Accessing nested JavaScript objects and arays by string path
... // strip a leading dot
var a = s.split('.');
for (var i = 0, n = a.length; i < n; ++i) {
var k = a[i];
if (k in o) {
o = o[k];
} else {
return;
}
}
return o;
}
Usage::
Object.byString(someObj, 'part3[0].name');
...
Flatten nested dictionaries, compressing keys
...t(items)
>>> flatten({'a': 1, 'c': {'a': 2, 'b': {'x': 5, 'y' : 10}}, 'd': [1, 2, 3]})
{'a': 1, 'c_a': 2, 'c_b_x': 5, 'd': [1, 2, 3], 'c_b_y': 10}
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Can the Unix list command 'ls' output numerical chmod permissions?
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it almost can ..
ls -l | awk '{k=0;for(i=0;i<=8;i++)k+=((substr($1,i+2,1)~/[rwx]/) \
*2^(8-i));if(k)printf("%0o ",k);print}'
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improv...
VC DDE（Dynamic Data Exchange）与EXCEL连接 - C/C++ - 清泛网 - 专注C/C++及内核技术
...的通信方案。花了半天时间研究了下，做了个案例，VC6.0下调试通过，很开心。作为一个产品经理，为产品设计搭建好平台，有人的平台，有技术平台，一切目标为了高效的做好产品。
该C++控制台程序案例如下：
// smdata.cpp : ...
Google Maps: how to get country, state/province/region, city given a lat/long value?
...ld look like:
http://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&sensor=false
Response:
{
"status": "OK",
"results": [ {
"types": [ "street_address" ],
"formatted_address": "275-291 Bedford Ave, Brooklyn, NY 11211, USA",
"address_components": [ {
...