Using Geojson to Draw a Map

2017-05-22

Why Leaflet

Leaflet is an open-source JavaScript library, which supply so many plugins we can use for map making.
Based on Leaflet, geojson is even more friendly to geo-data visualization. Tutorials are easy to follow.

Convert CSV to Geojson in Python

2017-05-22

What is Geojson

According to wikipedia, GeoJSON is an open standard format designed for representing simple geographical features, along with their non-spatial attributes, based on JavaScript Object Notation.

「译」JavaScript对象生命周期(Eloquent JavaScript 第六章)

2017-05-17

此文翻译《Eloquent Javascript》中第六章，The Secret Life of Objects，侵删。
该书有中文译本出版。此译文仅作交流学习之用。

How to Find Substrings in Python

2017-05-16

.find() function is used for find a substring in a string, and will return location index. E.g. -1 means no such substirng in this string.

How to Install PostgreSQL on a MAC

2017-05-14

Installation

Environment: macOS Sierra 10.12.4.

Install this database with ternimal:

Markdown Tools with Sublime

2017-04-25

Explorer entensions

Markdown here
Markdown here is an cross plantform extension for Chrome, Safari, Firefox and Thunderbird. It can help you write your email with markdown language quickly.
I am using Chrome extension for gmail. As long as I wrote my email in gmail interface, just hit Markdownhere button, then a nice formatted email will be there. That’s awesome.

「译」JavaScript正则表达式应用(Eloquent JavaScript 第九章)

2017-03-14

此文翻译《Eloquent Javascript》中第九章，Regular Expressions，侵删。
该书有中文译本出版。此译文仅作交流学习之用。

3D Convex Hull

2017-03-02

本方法适用于3D点云的凸包的提取，使用python实现。
这里用的方法是对quick hull做了一点小小的改进，主要分为两大块内容，初始化和迭代。

初始化

构建初始四面体

为了在初始化过程中构建一个相对比较大的四面体，我们需要分别找到6个最值点，分别是X，Y或者Z轴上的最大或者最小值点。找出6个点中距离最远的两个点，构建一条线。再找出距离这条线最远的点，构建一个面。再找出距离这个面最远的点，构建初始四面体。

Mac下tomcat的安装与配置

2017-02-07

下载及安装

下载并安装Java SE，下载对应版本的Tomcat，版本对应关系tomcat给出了文档. 我下载之后把apache-tomcat-7.0.75.zip放在Application目录下，方便起见改名为tomcat。mac应该下载tar.gz文件，zip文件会报错。
查看java版本

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