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David Beazley
2020-05-24 19:49:28 -05:00
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Notes/01_Introduction/01_Python.md
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@@ -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 Python in the shell, you will be able to use virtually everywhere
else. else.
## Exercises 1.1 ## Exercises
### (a) Using Python as a Calculator ### (a) Using Python as a Calculator

65
Notes/01_Introduction/02_Hello_world.md
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@@ -194,11 +194,10 @@ Comments are denoted by `#` and extend to the end of the line.
### Variables ### Variables
A variable is a name for a value. 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 `_`.
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.
Numbers can also be part of the name of a variable, except as the first character.
```python ```python
height = 442 # valid height = 442 # valid
@@ -221,7 +220,6 @@ height = 'Really tall' # A string
### Case Sensitivity ### Case Sensitivity
Python is case sensitive. Upper and lower-case letters are considered different letters. Python is case sensitive. Upper and lower-case letters are considered different letters.
These are all different variables: These are all different variables:
```python ```python
@@ -240,7 +238,6 @@ WHILE x < 0: # ERROR
### Looping ### Looping
Looping is a way to execute a set of instructions any number of times. 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: There are many ways to accomplish this in Python, one of them is the `while` statement:
```python ```python
@@ -257,7 +254,6 @@ The statements below the `while` will execute as long as the expression after th
### Indentation ### Indentation
Indentation in Python is used to denote a set of statements that go together. Indentation in Python is used to denote a set of statements that go together.
From our previous example: From our previous example:
```python ```python
@@ -277,25 +273,15 @@ The indentation means that the following statements go together under the `while
num_bills = num_bills * 2 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 ### Indentation best practices
print('Number of days', days)
```
The empty line is just for readability. It does not affect the execution. * Use spaces instead of tabs.
* Use 4 spaces per level.
### Blocks * Use a Python-aware editor.
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
```
Indentation within the block must be consistent. Indentation within the block must be consistent.
@@ -306,17 +292,6 @@ while num_bills * bill_thickness < sears_height:
num_bills = num_bills * 2 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 ### Conditionals
@@ -324,10 +299,10 @@ The `if` statement is used to execute a conditional:
```python ```python
if a > b: if a > b:
# `a` is greater than `b` # a is greater than b
print('Computer says no') print('Computer says no')
else: else:
# `a` is lower or equal to `b` # a is lower or equal to b
print('Computer says yes') print('Computer says yes')
``` ```
@@ -337,13 +312,13 @@ You can check for multiple conditions with the `elif`.
```python ```python
if a > b: if a > b:
# `a` is greater than `b` # a is greater than b
print('Computer says no') print('Computer says no')
elif a == b: elif a == b:
# `a` is equal to `b` # a is equal to b
print('Computer says yes') print('Computer says yes')
else: else:
# `a` is lower to `b` # a is lower to b
print('Computer says maybe') print('Computer says maybe')
``` ```
@@ -406,16 +381,12 @@ print('Your name is', name)
``` ```
`input` prints a prompt to the user and returns the response. `input` prints a prompt to the user and returns the response.
This is useful for small programs, learning exercises or simple debugging. This is useful for small programs, learning exercises or simple debugging.
It is not widely used for real programs. It is not widely used for real programs.
### `pass` statement ### `pass` statement
Sometimes you need to specify an empty block. Sometimes you need to specify an empty block. The keyword `pass` is used for it.
The keyword `pass` is used for it.
```python ```python
if a > b: 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. 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 ### (a) The Bouncing Ball

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Notes/01_Introduction/03_Numbers.md
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@@ -2,8 +2,6 @@
This section covers some basics of performing mathematical calculations in Python. This section covers some basics of performing mathematical calculations in Python.
## Reading
### Types of Numbers ### Types of Numbers
Python has 4 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). 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 > 17 digits or precision
> Exponent from -308 to 308 > 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. Be aware that floating point numbers are inexact when representing decimals.
```python ```python
@@ -128,7 +125,6 @@ abs(x) Absolute Value
``` ```
Theses are the same operators as Integers, except for the bit-wise operators. Theses are the same operators as Integers, except for the bit-wise operators.
Additional math functions are found in the `math` module. Additional math functions are found in the `math` module.
```python ```python
@@ -161,7 +157,7 @@ Try it out.
>>> >>>
``` ```
## Exercise 1.3 ## Exercises
### (a) Dave's mortgage ### (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 ### (c) Making an Extra Payment Calculator
Modify the program so that extra payment information can be more generally handled. Modify the program so that extra payment information can be more generally handled.
Make it so that the user can set these variables: Make it so that the user can set these variables:
```python ```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 ### (d) Making a table
Modify the program to print out a table showing the month, total paid so far, and the remaining principal. 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: The output should look something like this:
```bash ```bash