description: add new column to a dataframe

initial data

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a = pandas.DataFrame({'a':[1,2,3]})
# a
#    a
# 0  1
# 1  2
# 2  3

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b = pandas.DataFrame({'b':[2,4,6]})
# b
#    b
# 0  2
# 1  4
# 2  6

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c = pandas.DataFrame({'c':[1,2,3,4,5]})
# c
#    c
# 0  1
# 1  2
# 2  3
# 3  4
# 4  5

concat the same length

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pandas.concat([a,b], axis=1)
#    a  b
# 0  1  2
# 1  2  4
# 2  3  6

concat different length

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pandas.concat([a,c], axis=1)
#      a  c
# 0  1.0  1
# 1  2.0  2
# 2  3.0  3
# 3  NaN  4
# 4  NaN  5

description: unable to install Sql Server with exit code 1638

solution

• exit code 1638 means a newer version of Microsoft Visual C++ has been installed
• uninstall 2015, 2017 and others higher than 2015
• restart the process

problem description

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TITLE: Microsoft SQL Server 2017 Setup
------------------------------

The following error has occurred:

VS Shell installation has failed with exit code 1638.

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description: simplest example for LSTM ANN in python

import packages

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import numpy
from keras.models import Sequential
from keras.layers import Dense
from keras.layers import LSTM
import matplotlib.pyplot as plt

initial dataset

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test_set = [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8]
dataset = []
for i in range(1, 100):
    dataset.append(i%10/10)

transform data into [current_data, next_data]

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dataX, dataY = [], []
for i in range(len(dataset) - 2):
    dataX.append(dataset[i])
    dataY.append(dataset[i + 1])
dataX = numpy.array(dataX)
dataY = numpy.array(dataY)

reshape data

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dataX = numpy.reshape(dataX, (dataX.shape[0], 1, 1))

create and fit the LSTM network

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model = Sequential()
model.add(LSTM(4, input_shape=(1, 1)))
model.add(Dense(1))
model.compile(loss='mean_squared_error', optimizer='adam')
model.fit(dataX, dataY, epochs=10, batch_size=1, verbose=2)

make predictions

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test = numpy.array(test_set)
test = numpy.reshape(test, (test.shape[0], 1, 1))
trainPredict = model.predict(test)

plot baseline and predictions

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plt.plot(test_set)
plt.plot(trainPredict)
plt.show()

description: convert array into a list in java

convert array into list

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ArrayList<Object> list = new ArrayList(Arrays.asList(yourArray));

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change index.swig file

under your-hexo-site\themes\next\layout

chang the title codes

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{% block title %}{{ config.title }}{% endblock %}

change into

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{% block title %}{{ config.title }} - {{ theme.description }}{% endblock %}

moreover, it can add keywords into title

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{% block title %}{{ theme.keywords }} - {{ config.title }} - {{ theme.description }}{% endblock %}

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install hexo-generator-feed

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$ npm install hexo-generator-feed --save

add following contents into _config.yml

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feed:
  type: atom
  path: atom.xml
  limit: 20
  hub:
  content:
  content_limit: 140
  content_limit_delim: ' '

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build a new adsense template under next theme in layout/_custom

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themes/next/layout/_custom/google_adsense.ejs

put the google adsense codes into google_adsense.ejs

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<script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
<script>
  (adsbygoogle = window.adsbygoogle || []).push({
    google_ad_client: "ca-pub-5817381835091099",
    enable_page_level_ads: true
  });
</script>

add following codes in _layout.swig under theme folder

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<!-- Google AdSense start -->
{% include '_custom/google_adsense.ejs' %}
<!-- Google AdSense end -->

generate web page and check source file to see the google code in there

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description: hexo deploy github pages through ssh

configuration for deploying to github with ssh

change the configuration in _config.yml under the hexo root folder

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# Deployment
## Docs: https://hexo.io/docs/deployment.html
deploy:
  type: git
  repository: git@github.com:kelfan/kelfan.github.io.git
  branch: master

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install plugin for SEO sitemap

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npm install hexo-generator-sitemap --save

optional for baidu search engine

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npm install hexo-generator-baidu-sitemap --save

change configuration file in _config.yml

add following codes into _config.yml file and change the value of url, should be like http://yoursite.com

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sitemap:
    path: sitemap.xml

url: https://search4fan.github.io

optional for baidu search engine sitemap

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baidusitemap:
    path: baidusitemap.xml

check with public folder

after hexo g, the sitemap.xml or baidusitemap.xml should be found under public folder

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description: add a local search for hexo blog

install hexo-generator-search

run following commend under search4fan.github.io/ folder

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npm install hexo-generator-search --save

change configuration

add following text in search4fan.github.io/_config.yml

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search: 
      path: search.xml
      field: post

change theme configuration

change _config.yml under theme folder search4fan.github.io/themes/next/_config.yml

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# Local search
# Dependencies: https://github.com/theme-next/hexo-generator-searchdb
local_search:
  enable: true
  # if auto, trigger search by changing input
  # if manual, trigger search by pressing enter key or search button
  trigger: auto
  # show top n results per article, show all results by setting to -1
  top_n_per_article: 1
  # unescape html strings to the readable one
  unescape: false

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