MIT 计算机科学及编程导论 Python 笔记 1
计算机科学及编程导论在 MIT 的课程编号是 6.00.1，是计算机科学及工程学院的经典课程。之前，课程一直使用 Scheme 作为教学语言，不过由于 Python 简单、易学等原因，近年来已经改用 Python 作为教学语言了。更多介绍
最初知道这个课程的时候大概是在 2014 年，对于做事拖沓的我，这门课程已经从低清随堂录制变成了 edX 平台的一门 高清的 MOOC，转眼间已经大三，希望自己能够完成自己曾经定下的计划。以下是在我在学习本课程时的一些笔记，在此与大家共享、共勉。
What does a computer do?
-
Fundamentally a computer:
- Performs some calculations
- Remembers results
-
What calculations?
- Built in primitives
- Creating our own methods of calculating
Simple calculations are not enough, so good algorithm design also needed to accomplish a task.
Despite its speed and storage, a computer does have limitations
- Some problems still too complex
- Some problems are fundamentally impossible to computer (e.g. Turing's Halting Problem)
Knowledge
- Declarative
- Imperative (likes a recipe, "how-to")
Computers
-
Fixed-program computers (earliest computers)
To solve specific problems- Atanasoff (1941) - linear equations
- Turing bombe
-
Stored-program computers
-
Program is a recipe. Each programming language provides a set of primitive operations.
-
Given a fixed set of primitives, a good programmer can program anything.
-
Anything you can do with a language, you can do with another.
About python
- High(√) vs. Low
- General(√) vs. Targetted
- Interpreted(√) vs. Compiled
Aspects of languages & Common Errors
| Aspects | Description |
|---|---|
| Primitive constructs | numbers, strings, simple operators |
| Syntax | which strings of charactres and symbols are well-formed |
| Static semantics | which syntactically valid strings have a meaning |
| Full semantics | what is the meaning associated with a syntactically correct string of symbols with no static semantic errors |
- 语法用来描述语言中，什么表述是合法的。
- 静态语义表示什么程序是有意义的，哪种表达是有意义的。
- 完整语义即程序想达到什么目的，运行程序会产生什么效果。
Goal
- Learn the syntax and semantics of a programming language.
- Learn how to use those elements to translate “recipes” for solving a problem into a form that the computer can use to do the work for us.
- Computational modes of thought enable us to use a suite of methods to solve problems.
