# Programming Language and Execute Python Code

Pages: 2 (434 words) Published: October 27, 2014

Chapter1. Introduction

① Data
② Algorithm:
Precise sequence of steps carrying out a task
(执行任务的精确步骤)
③ Programming:
A program/software implements the algorithm that
will operate on our data.(执行管理数据的计算程式) ④ Abstraction:
When designing one part of a program, we can
ignore the inessential details of other parts of
the program as long as we have a high level
understanding of what they do. (提取)
★作用/重要性：一个人不必关注所有事物，仅替换一个 因素就可更新，有条理的检测软件
⑤ Problem solving and Creative
State (状态) : Internal information that describes what a computer is doing. Picobot执行的移动路线：初始state永远为0，到达state 为0-99. “x”表示该方向没有障碍物，NEWS指北东西南有障碍物。 书写形式：0 xxWx → E 1 表示Picbot在西面有障碍物的情况下向东走到的区域是1。 0 xxxx → W 0 表示Picbot在四面都没障碍物时，向西接着走到的区域是0。 1 xxxx → E 1 表示在走的过程中走到1时，四面都没障碍物，则向东面接着走到的区域仍为1。 1 xExx → W 0 表示在走的过程中走到1时，当东面有障碍物，则向西走到的区域为0。0 Nxxx → X 1 表示从0出发，当北面有障碍物时，原地不动，但该位置变成1。 ★ 当只考虑一个方向有无障碍物时，其他方向可用未知数代替，如**W*，指不论其他方向如何，只要满足西面有障碍物即可。 Right-hand-rule

1st’rule：当面对一个方向（北）时右手边有墙，则向面对的方向走，没墙则向右手边走。 2ndrule：当面对上述方向（北）时，面对方向有墙右边也有墙，设计转方向。3rd rule：similar sets of rules for the other three facing directions. 需要满足的客观条件：不能在意起点，所有靠墙的cell都连着外墙, 所有空cell都挨着wall。 How to think like a computer scientist

Python is a high-level language.
Low-level language can be called machine or assembly language.(encoding in binary计算机运行的二进制). 电脑只能直接执行low-level language编写的program，high-level have to be processed before run. 2.High-Level 的好处
①easier to program；take less time to write； shorter
and easier to read； more likely to be correct.
②high-level languages are portable,
can run on different kinds of computers with few or no modifications. 3.terpreters & compilers:
high-level into low-level.
★ High-level program: source code
Translated program: object code/executable