From f98e99b6cb9ab6571d0c30c8ba78721293ce9d5a Mon Sep 17 00:00:00 2001 From: David Beazley Date: Sun, 24 May 2020 19:49:28 -0500 Subject: [PATCH] Edit --- Notes/01_Introduction/01_Python.md | 2 +- Notes/01_Introduction/02_Hello_world.md | 65 +++++++------------------ Notes/01_Introduction/03_Numbers.md | 10 +--- 3 files changed, 21 insertions(+), 56 deletions(-) diff --git a/Notes/01_Introduction/01_Python.md b/Notes/01_Introduction/01_Python.md index af002c9..78778e0 100644 --- a/Notes/01_Introduction/01_Python.md +++ b/Notes/01_Introduction/01_Python.md @@ -59,7 +59,7 @@ shell. This is Python's native environment. If you are able to use Python in the shell, you will be able to use virtually everywhere else. -## Exercises 1.1 +## Exercises ### (a) Using Python as a Calculator diff --git a/Notes/01_Introduction/02_Hello_world.md b/Notes/01_Introduction/02_Hello_world.md index 0f4d45c..13c0180 100644 --- a/Notes/01_Introduction/02_Hello_world.md +++ b/Notes/01_Introduction/02_Hello_world.md @@ -194,11 +194,10 @@ Comments are denoted by `#` and extend to the end of the line. ### Variables -A variable is a name for a value. - -You can use letters (lower and upper-case) from a to z. As well as the character underscore `_`. - -Numbers can also be part of the name of a variable, except as the first character. +A variable is a name for a value. You can use letters (lower and +upper-case) from a to z. As well as the character underscore `_`. +Numbers can also be part of the name of a variable, except as the +first character. ```python height = 442 # valid @@ -221,7 +220,6 @@ height = 'Really tall' # A string ### Case Sensitivity Python is case sensitive. Upper and lower-case letters are considered different letters. - These are all different variables: ```python @@ -240,7 +238,6 @@ WHILE x < 0: # ERROR ### Looping Looping is a way to execute a set of instructions any number of times. - There are many ways to accomplish this in Python, one of them is the `while` statement: ```python @@ -257,7 +254,6 @@ The statements below the `while` will execute as long as the expression after th ### Indentation Indentation in Python is used to denote a set of statements that go together. - From our previous example: ```python @@ -277,25 +273,15 @@ The indentation means that the following statements go together under the `while num_bills = num_bills * 2 ``` -Because the next statement is not indented, it means that it does not belong to the previous set. +Because the next statement is not indented, it means that it does not +belong to the previous set. The empty line is just for +readability. It does not affect the execution. -```python -print('Number of days', days) -``` +### Indentation best practices -The empty line is just for readability. It does not affect the execution. - -### Blocks - -A block is a set of statements grouped together. - -In our previous example, the statements within the `while` form a *block*. - -```python - print(day, num_bills, num_bills * bill_thickness) - day = day + 1 - num_bills = num_bills * 2 -``` +* Use spaces instead of tabs. +* Use 4 spaces per level. +* Use a Python-aware editor. Indentation within the block must be consistent. @@ -306,17 +292,6 @@ while num_bills * bill_thickness < sears_height: num_bills = num_bills * 2 ``` -The character colon `:` indicates the start of a block and must be present. - -```python -while num_bills * bill_thickness < sears_height: -``` - -### Indentation best practices - -* Use spaces instead of tabs. -* Use 4 spaces per level. -* Use a Python-aware editor. ### Conditionals @@ -324,10 +299,10 @@ The `if` statement is used to execute a conditional: ```python if a > b: - # `a` is greater than `b` + # a is greater than b print('Computer says no') else: - # `a` is lower or equal to `b` + # a is lower or equal to b print('Computer says yes') ``` @@ -337,13 +312,13 @@ You can check for multiple conditions with the `elif`. ```python if a > b: - # `a` is greater than `b` + # a is greater than b print('Computer says no') elif a == b: - # `a` is equal to `b` + # a is equal to b print('Computer says yes') else: - # `a` is lower to `b` + # a is lower to b print('Computer says maybe') ``` @@ -406,16 +381,12 @@ print('Your name is', name) ``` `input` prints a prompt to the user and returns the response. - This is useful for small programs, learning exercises or simple debugging. - It is not widely used for real programs. ### `pass` statement -Sometimes you need to specify an empty block. - -The keyword `pass` is used for it. +Sometimes you need to specify an empty block. The keyword `pass` is used for it. ```python if a > b: @@ -426,7 +397,7 @@ else: This is also called a "no-op" statement. It does nothing. It serves as a placeholder for statements. Possibly to be added later. -## Exercises 1.2 +## Exercises ### (a) The Bouncing Ball diff --git a/Notes/01_Introduction/03_Numbers.md b/Notes/01_Introduction/03_Numbers.md index 64882c8..70ccb0d 100644 --- a/Notes/01_Introduction/03_Numbers.md +++ b/Notes/01_Introduction/03_Numbers.md @@ -2,8 +2,6 @@ This section covers some basics of performing mathematical calculations in Python. -## Reading - ### Types of Numbers Python has 4 types of numbers: @@ -95,12 +93,11 @@ c = -1.345e-10 ``` Floats are represented as double precision using the native CPU representation [IEEE 754](https://en.wikipedia.org/wiki/IEEE_754). +This is the same as the `double` type in the programming language C. > 17 digits or precision > Exponent from -308 to 308 -This is the same as the `double` type in the programming language C. - Be aware that floating point numbers are inexact when representing decimals. ```python @@ -128,7 +125,6 @@ abs(x) Absolute Value ``` Theses are the same operators as Integers, except for the bit-wise operators. - Additional math functions are found in the `math` module. ```python @@ -161,7 +157,7 @@ Try it out. >>> ``` -## Exercise 1.3 +## Exercises ### (a) Dave's mortgage @@ -198,7 +194,6 @@ When you run the new program, it should report a total payment of `929,965.62` o ### (c) Making an Extra Payment Calculator Modify the program so that extra payment information can be more generally handled. - Make it so that the user can set these variables: ```python @@ -214,7 +209,6 @@ How much will Dave pay if he pays an extra $1000/month for 4 years starting in y ### (d) Making a table Modify the program to print out a table showing the month, total paid so far, and the remaining principal. - The output should look something like this: ```bash