204 IT: Python Coding Course (204.html)

Keywords

IX or DC (IX by DC) or "|><"

Introduction

Course Topics (By Day)

• 1. First Coder and Computer, Punched Cards
  Numeric, String Variables, Literals, Lists
  Statements: =, print, while, input
• 2. Numbers: Integer, Float, Scientific Notation
  print formatting Arithmetic: + - * / **
• Boolean and Logic:
  True and True
  True and False
  False and True
  False and False
• Boolean or Logic:
  True or True
  True or False
  False or True
  False or False
• boolean operators: and or not
• E = I*R (Image 3)
• LED
• 3. Circuit Logic
  Print Formats
  Valves & Transistor
  Statement: function
• Python String Methods (Source 04)

 Day 1 

a = 2
print(a)
a = 6
print(a)
cList = []
cList = ["Ford", 2, "Joe"]
print(cList)
cList.append("347")
print(cList)
print(len(cList))

 Day 2 

x = 3/2
print(x)
x = 3/20
print(x)
x = 3/200
print(x)
x = 3/2000
print(x)
>>>0.0015
x = 2000/3
print(x)
>>>666.66666666

x = 12345678901234567890
y = x * 100000000000000000
print(y)
>>>1.2345678901234568e+36

cList=["a", "b", "c", "d"]
print(cList[2])
>>>c
dList=[2,4,6,8,111,12,14]
print(dList[2:5])
>>>6,8,111,12
eList=list((8,111,12))
print(eList)
>>> 8,111,12

 print without format 
name = "Eric"
print("Hello,", name, ".")
>>> 'Hello, Eric .'


 print with placeholder and % 
name = "Eric"
print("Hello, %s ." % name)
'Hello, Eric .'

 print with format 
name = "Eric"
txt = "Hello, {}."
print(txt.format(name))
>>>Hello, Eric.

price = 49
txt = "The price is {:.2f} dollars"
print(txt.format(price))
>>>The price is 49.00 dollars

txt = "The price is {:7.2f} dollars"
print(txt.format(price))
>>>The price is    49.00 dollars

price = 49111
txt = "The price is {:9.2f} dollars"
print(txt.format(price))
>>>The price is  49111.00 dollars

price = -49111
print(txt.format(price))
>>>The price is -49111.00 dollars

import subroutines

import time

while True :
    time.sleep(2)
    print("after 2 seconds")
#while end
>>>after 2 seconds
>>>after 2 seconds
>>>after 2 seconds
ctrl-C or ctrl-D

Turn On LED using Zero_led.py

#Zero_led.py
import time
from gpiozero import LED
led = LED(14)         # GPIO 14 = phys pin 08
# lead with no resistor is ground phys pin 06
while True:
    led.on()
    time.sleep(1)
    led.off()
    time.sleep(1)
# done 
#************************************************

Day 3

aStr="    abc    "
print(aStr)
bStr = aStr.strip()
print(bStr)

TURN ON LED Using Pushbutton

import time import RPi.GPIO as GPIO 
# Pins definitions
 btn_pin = 4 
led_pin = 12 # Set up pins 15 
GPIO.setmode(GPIO.BCM) 
GPIO.setup(btn_pin, GPIO.IN) 
GPIO.setup(led_pin, GPIO.OUT) # If button is pushed, light up LED 
try: 
     while True: 
         if GPIO.input(btn_pin): 
             GPIO.output(led_pin, GPIO.LOW) 
         else: 
             GPIO.output(led_pin, GPIO.HIGH) 
# When you press ctrl+c, this will be called 
finally: GPIO.cleanup()

Work or Energy joule: unit of work or energy in the International System of Units (SI); it is equal to the work done by a force of one newton acting through one metre. Named in honour of the English physicist James Prescott Joule, it equals 107 ergs, or approximately 0.7377 foot-pounds. 1 joule = 10**7 ergs = 0.7377 foot-pounds.

See Images 01 and 02. 1 watt = 1 joule / sec = 1kg·m²·s**-3

Images

Periodic Table

LED (flat [short leg]: ground)

Diode Depletion Regions

Diode Curve

Image 03 E = I * R

NPN

NPN depletion regions

PNP current components

Day 4

Day4
Escape characters
   https://www.w3schools.com/python/python_strings_escape.asp
Assembly Language- RPi
   file:///home/pi/Downloads/MagPi116.pdf
7bit Ascii 
   https://en.wikipedia.org/wiki/ASCII#/media/File:USASCII_code_chart.png
JSON example
    JSON_example.txt (See Source 07)
fwrite2.py
SQL DataBase
SQL

Day 5

                     Feynman        666
              9 |     999999       + 96
              
                     -------      -----
           9999999   1722766        762  <- Feynman Number

Feynman Diagram

Day5
   Tristan02.py
       iGalri.html
       PythonINFO_prettify.txt
         use Geany vs
       PythonINFO_prettify.html    

   Geany html
         json
         py
   Serial ASCII
      http://ephotocaption.com/a/179/179.html
     See YouTube Video (Video Source 01 ) to view serial data on an oscilloscope.




						(To enlarge .....Click it)
			
			

			

			Ascii Data On An Oscilloscope
	



  ordAscii.py output
     The ASCII value of 'p' is 112 in base 10
     ch = 'p'
     ch in hex    is x70.
     ch in octal  is o160.
     ch in binary is 1110000
     The price is 112.00 dollars

ordAscii.py source
	# Program to find the ASCII value of the given character
	progName="ordAscii.py"

	ch = 'p'
	print("The ASCII value of '" + ch + "' is", ord(ch))

	print("ch = 'p'")
	print("ch in hex    is x%x." % ord(ch))
	print("ch in octal  is o%o." % ord(ch))
	#print("ch in binary is 0b%0b." % ord(ch))
	chInt = 112
	# ? format number as binary (in base 2)
	string = "ch in binary is "+ f'{chInt:b}'
	print(string)  		# 1110000

	price = 112
	txt = "The price is {:.2f} dollars"
	print(txt.format(price))




   strElements.py
progName: strElements.py
strTest:     #abcdef
strTest[0:7] #abcdef
len(strTest) 7
lenStr=len(strTest)
strTest[0:lenStr] #abcdef
strTest[0:0] 
strTest[0:1] #
strTest[1:2] a         #new
strTest[1:3] ab        #new
strTest[0:-1] #abcde
strTest[0] #
strTest[1] a
strTest[-1] f
strTest[-lenStr] #
strTest[1:-1] abcde
strCap=strTest[1:-1].capitalize() Abcde

    iGal_co0001i.txt
    iGal_co0001i.html

/Days4_and_5.txt

Day 6 : Coding Exercises

Ex01.py
Purpose to reverse the words in a sentence
1. Create a file named Ex01Data.txt containing two rows of words
    eg   saw  kitten joe
           gniht yraM miT
2 crete a function that accepts a word (containing no spaces)
    the function should return the word spelled backwards
3. Write a program that reads the file Ex01Data.txt separates
   each word, calls the function to spell the word backwards
4. prints each resulting line on the screen. . . eg
     eg     was nettik eoJ
            thing Mary Tim

Ex02.py
Purpose: to "draw" a letter on the screen
1. Create a function that accepts a single character
    eg "a"
   It returns a string that "draws" the character
    eg   " xxxx x\n
          xx  xxx\n
          xx  xxx\n
          xx  xxx\n
           xxxx x\n"

2. Write a program that calls the function passing
   the character eg "a".  The subroutine will return
   the "drawing" of the character.  The program then
   prints the drawing of the character on the screen
   using the print statement.

Ex03.py
Purpose: To send Morse Code using the LED.
1  Write a program that flashes a character using 
   Morse Code.  
        e  .     i  ..    s ...
        t  -     m  --    o ...
   It will blink the LED to display the character.
2. The program will first ask the user how long a 
   dot (.) should be.  eg .5  means ".5 seconds"
   A dash (-) should be the length of 3 dots.
   The time between 2 parts of a character should be
   2 dot times
   The time between 2 characters should be at least
   2 dash times.
3. The program asks the user to input one or more
   of the six characters above above to form a word.
   eg   "mom"   "time"  or "i"
4. The program will call a function sending it each character 
   in the word.  The function will turn on and off the
   LED to "send" the character in Morse Code.
5. The program will get the user to input a "word"
   and will call the subroutine to "send" each 
   character of the word in Morse Code.
6. To test the program, just "watch" the LED blinking.

HINT:  Use a Python dictionary to store the characters.
   Also put the following in the dictionary
   "/"  is the sleep time between 2 parts of a character
   " "  is the sleep time between 2 characters.

Refer to Source 08 to hear Morse Code audibly.

Day 7

OHM's law

E = I x R ........ E(volts) = I(amps) x R(ohms)

Resistance of 2 Resistors in Series.

LED symbol

LED (flat [short leg]: ground)

What is a CdS cell?

~    500 ohms	in direct sunlight
~  5,000 ohms	in a lit room
~500,000 ohms	in the dark

CdS Light-Dependant Resistor (PhotoCell)

The digLight Python circuit for the Raspberry Pi

wire                         GPIO      Phys
color  to                     pin       pin
*****  ********************* ****      ****
red    CdS cell               3V3        17
yellow S to 10K Var. Resist.   17        11
green  Ground                 GND         9

Adjust 10K Var. Resist. to be 6K8 ohms

Inverted ambLight/digLight sensor (KY-018 Schematic)

:94 CdS photo-resistor w 5K6 resistor for BreadBoard

:95 CdS photo-resistor w 10K0 resistor for RPi

Dupont Connectors

Dupont Connectors (with Male end)

Program to read ambient light as 1 or 0

import RPi.GPIO as GPIO
import time

progName="digLightTest.py"
print("starting ",progName)
print(" Ctrl-C will end the program")
digLight_pin=17  #GPIO pin 17 is physical pin # 11 on the Raspberry Pi
# verified by Tristan Marcoux on 2023GJul25
#  CdS is connected between digLight and nominal 3V3 which is often 3.75v
#  6.8k resistor is connected between digLight and GND.
# 10k   resistor is too high when the back and sides of the CDS are not kept dark.
#  The 6.8k resistor even detects between dim light and dark.
#  It is recommended to use a 10k0 rheostat (variable resistor) initially set to 6K8.
#setup the pins in the software
GPIO.setmode(GPIO.BCM)
GPIO.setup(digLight_pin,GPIO.IN)
try:
	while True:
		if GPIO.input(digLight_pin):
			print("digLight is 1: ON  i.e. lit")
		else:
			print("digLight is 0: OFF i.e. dark")
		#if end
		time.sleep(1) #sleep for 1 second
	#while end
finally:
	print("ending ",progName)
#try end
# /digLightTest.py
#program end

On-Line Book: Pico Tips and Tricks (Source 10)

Pull-down, Pull-up and Floating connections (Corrected)

• on-board (Pico) green LED
• WiFi
• hosting a web-page
• reed switch
• servo motor
• non-servo motor
• Maker drive board (US$4.32 Source 12)
• stepper motor
• SD or micro-SD card
• MQ series Gas Detector
• Distance Measurement
• on-board (Pico) Temperature
• DS18B20 temperature sensor
• AHT10 Temp & Humidity sensor
• Motion Sensing with a PIR sensor
• HC-SR501 sensor
• AM312 sensor
• vibration sensors
• Piezoelectric vibration sensor
• IMU sensor
• 3-axis Accelerometer sensor
• GY-521 IMU module using a MPU-6050 sensor
• OLED display
• the ssd1306 PyPI module
• a dot matrix display
• addressable LEDs
• Prometheus and Grafana
• Sending an email (see Source 13)
• Real Time Clock (RTC)
• Universal LED blink

Day 8 Using Terminal and SORTING

SOME TERMINAL COMMANDS

See Source 24 for more information about the Raspberry Pi OS .
Source 22 describes all of the Linux commands including those below eg "sort".

folders: Desktop/Day8

cat a b >c                 # concatenate files
cd  newdir                 # change directory
cp a b                     # copy a file
dir                        # directory list
grep "string" tFile        # display line containing "string" in tFile
grep --help                # display grep options and examples
ls                         # list directory 
more tFile                 # display a tFile
nano tFile                 # edit tFile in Terminal
rm  aFile                  # remove (delete) tFile
sort tFile >bFile          # sort tFile into bFile 
sort --help                # display help options and examples
^ arrow                    # previous (up)
v arrow                    # next (down)
< arrow                    # left
> arrow                    # right
Enter to execute           # run the command as showing

See Source 28 (my Article 170)  for a longer list (of 50 Useful Linux Terminal Commands).

Exercises for Sorting Manually

Sort order is according to ASCII character numerical order.


1A. Create a file named "fox.txt" (one word per line) containing:

the quick brown fox jumps over the lazy dog

1B. Use "grep" to find a record starting with string "jum"

    > $ grep "jum" fox.txt

2. Use a text editor to sort the words ("brown" should be first).

3. Write it out with the name "fox_sorted.txt"

4. Write a Python program to sort any text file (at end of lecture).

5. Use nano in Terminal to manually sort the file 

   > $ cd Desktop/Day8
       cp fox.txt fox_s.txt
       nano fox_s.txt
       Ctrl-o
       Ctrl-z

6. use sort in Terminal to sort the file
   > $ cd Desktop/Day8
       sort fox.txt >fox_sort2.txt

7. use cat to create a file named file1
   > $ cd Desktop/Day8
       cat >file1
       rrrrrr
       xyz
       Ctrl-d

8. use cat to create a file named file2
   > $ cd Desktop/Day8
       cat >file2
       abc
       Ctrl-d

9. use "dir" and "ls" to display the Directory
   > $ dir
       ls
       cd Desktop/Day8
       dir

10. use "more" to display file1
    > $ cd Desktop/Day8
        more file1

11. use "cp" to copy file1 to file3
    > $ cd Desktop/Day8
        cp file1 file3
        ls
        more file3
        Ctril-c

12. use "rm" to delete file3
    > $ cd Desktop/Day8
        rm file3
        ls

13. use "|" for piping
   use cat to join 2 files, show the result, then sort them
   > $ cd Desktop/Day8
       cat file1 file2 > file4
       ls
       more file4

   > $ cat file1 file2 | sort file5
       ls
       more file5

14. Display sort help
   > $ sort --help

    Also see Source 23 for the "sort" section of Linux Man7 Manual (Source 22)

   > $ help sort
       SYNTAX
       sort [OPTION]... [FILE]...
       sort [OPTION]... --files0-from=F

       OPTIONS
       -b         ignore leading blanks
       . . . 
       -r         reverse sort results
       -c         check for sorted input; do not sort
       -o fText   write output to fText file
       etc

Program (Algorithm) to sort a text file

     Name it mySort.py
     0. Create a function named sort2(a,b) to compare 2 records (text strings)
            and return the lowest (the record to appear first when sorted)
        Test this function using a small test program

     Write the mySort.py program to do the following:
     1. recNA=1
     2. Open the input file
     3. lenN= number of records in input file
     4. copy each record into an element of an array named rList
           rList=[]   # empty list (array)
           recN=0
           for rec in file1:
              recN=recN+1
              rList[recN] = rec
           #for end
           display the list of records to be sorted
           print("rList:",rList)
     5. Close the input file
     6. Open the result file (initially empty)
     7. Find the lowest (when sorting) record in rList (using sort2 function)
     8.    Write this record to the output file
     9.    Set this lowest record in rList to Null
     10.          so that it will be effectively "removed" from rList.
     11.   Repeat at step 7 to find the next lowest record
                in rList.
     12.   Stop doing this when rList is empty (when all rlist records are null.
     13.   When done, close the result file
     14.   display the result file.

     See Sources 20 and 21 for better Python programs to sort a text file
     Other algorithms are a bubble sort and a Hashed key file sort.

Day 9

9.1 Create a String Sort program using the Python function "lowest()" from Source 32.
     [lowest() returns the position of the lowest non-nul item, if any, in a list of strings.]

9.2 Connect and use a small powerful Raspberry Pi Zero-2-W (below).

9.3 Review the "Python CheatSheet" in Source 31 to identify "new" concepts.

9.4 Review "Raspberry Pi Benchmarks" in Article 170.

9.5 See the MagPi Magazine article "Learn Python..." on p77 in Source 30.

Day 10

Day 11

Day 12

For each string of letters that are input:

a) how many capital letters are there?
b) how many non-capital (lower case) letters are there?
c) how many digits are there?
d) how many other letters are there?
    "other" means not capital, not non-capital, not digits.
      examples are "$&() etc"
e) how many spaces are there?
f) what is the highest digit in the string?
g) how many characters are vowels?

h) If "Boo" is in the string, print out "Boo" and exit the program

Extra Difficulty
i) what is the highest integer in the string?
    example "A431C998a$47." highest integer is 998
j) Only in the case of a string of 4 lower case letters; 
  print out all three letter words that can be generated
  using only the lower case letters. These three letter
  words must be of the form: non-vowel, vowel, non-vowel
  All words from the string "xopt" would be:
     xop
     xot
     top
     pox
     tox
     pot
     xox
     pop
     tot
  All words from the string"mopi" would be:
   mop
   mip
   pom
   pim
   mom
   mim
   pop
   pip

Day 13

Exercise 56B

Raspberry Pi Zero-2-W

Raspberry Pi Zero-2-W

Recommended "Onboard" keyboard for the Raspberry Pi

Onboard keyboard on BullsEye OS

Of the many versions of Onboard available for the Raspberry Pi, I installed onboard-1.4.1-5+b3 (64 bit) on 2023HAug27.
To invoke Onboard, click on "Universal Access" in the Accessories submenu
Some characters are not in the expected positions (compared to the Raspberry Pi keyboards):
 The "\" is to the left of the "Enter" key
 The "|" is "shift-\"
 The "<" appears to the left of the "z" key and elsewhere on other layouts
Feature: "Alt-Gr-F dhighlighted the Subfile "F" menu (like "ctrl-f") in the Raspberry Pi text editor.
Feature: A tiny "mobile" keyboard layout is available for tiny displays.
Feature: Click on the three horizontal bars (bottom right corner) to access the Snippets.
Feature[?]: My Snippets were not lost when I uninstalled and re-installed Onboard.
Feature: Clicking on the "X" in the top right corner toggles Onboard from the display.
Feature: Snippets can be viewed and deleted using the "Tools" button
  But any snippet text defined using "Tools" are not retained; they must be re-entered.

Onboard Source, Author & Interactions

Onboard Linux Manual and Issues

	>$ man 1 onboard
	

	>$ ls \n
	

Handling of Control Files during Software Installs & Uninstalls

Related Thoughts

Sources

Video Sources

Web Sources

www

W3 Python Lists

www

Semiconductor Doping

www

Semiconductor Diode Operation

www

Python String Methods

www

Transistor Currents

www

Diodes

www

JSON squad example

www

Morse Code Generator

www

A&C: PiR2Null Area Controller (153)

www

Raspberry Pi Pico Tips and Tricks (>100 p)

www

IX Device Inventory at 621ON

www

Cytron Maker Drive Datasheet

www

emailSender_py.txt

www

RPi Pico W DataSheet (25 p)

www

nxp 74hct9046a VCOsc Datasheet

www

LM386 Audio Amp Circuit

www

LM386 Audio Amp DataSheet

www

ESP-01 (Using the ESP8266 Module)

www

SwitchDoc Labs Product Pages and Documentation Archive

www

sortF.py as txt

www

sortFquik.py as txt

www

The Linux Programming Interface

www

SORT OPTIONS from The Linux Programming Interface

www

Raspberry Pi OS Documentation

www

Raspberry Pi Zero 2 W Specs

www

Raspberry Pi Zero 2 W product brief (6 pp)

www

Raspberry Pi Zero 2 W schematics and board specifications

www

Pi: Useful Raspberry Pi Device Family Terminal Commands (170.html)

www

IT: Flash Drive & Device Library (167.html)

www

Pi: MagPi Magazine Issue 132

www

IT: Python cheatsheet

www

Pi: lowest.py (stored as *.txt)

www

Onboard Help (CLI)

www

Onboard Linux Manual

www

Launchpad.net Onboard Website

www

Raspberry Pi Commands

www

Raspberry Pi Glossary

www

10 Python Programs to Write

www

Bluetooth on Pico W

www

Bluetooth on Pico W

www

Python Basic Exercise for Beginners