3.3 Expressions(Show video 1 and 3)

Vocab: fill in the blanks

the symbol for exponent is *
the symbol for addition is +
the symbol for subtraction is -
the symbol for multiplication is __
the symbol for division is /
the symbol for modulus is %
an algorithm is a series of operations that completes a task/solves a problem __

Sequencing Practice: the code below does not follow the intended steps below. change the code so that it does so.

  1. divide value1 by 10(value1 = 5)
  2. multiply 2 from the result of the step 1
  3. subtract 4 from the result of the step 2
  4. print the result of step 3
value1 = 5
value2 = value1 / 10 #step 1
value3 = value2 * 2 #step 2
value4 = value3 - 4 #step 3
print(value4)

-3.0

Selection/Iteration Practice: Create a function to print ONLY the numbers of numlist that are divisble by 3.
Hint: use the MOD operator (a % b) to find the remainder when a is divided by b.

numlist = "3","4","9","76","891"
for num in numlist:
    if int(num) % 3 == 0:
        print(num + " is divisible by 3")
        continue
    else:
        print(num + " is not divisible by 3")
        continue

3 is divisible by 3
4 is not divisible by 3
9 is divisible by 3
76 is not divisible by 3
891 is divisible by 3

Homework/Binary Adaptation: Create a python function that will convert a decimal number 1-255 to binary using mathematical operations and powers of 2. Challenge: add frontend with javascript or html.

def convert(num): #defines the variable and convert(x) function
    result = "" #"" = what will be printed 
    i = 7
    while (256 > i > 0): # creates the while loop which determines whether the number is even or odd and assign the binary 1 or 0s for the final print
        if num % (2**i) == num: 
            result = result + "0"
            i -= 1
        else:
            result = result + "1"
            num -= 2**i
            i -= 1
    print(result) # print the result defined in line 2
convert(66) # conversion from line 1

0100001

3.4 Strings(Show video 1)

Vocab: fill in the blanks using the video

Index is a number representing a position, like a character's position in a string or a string's position in a list.
Concatenation is combination of strings Length is number of characters in the string
A substring is _ part of a string __

What is psuedocode?

Pseudocode is writing out a program in plain language with keywords that are used to refer to common coding concepts.

Can you think of some benefits of using pseudocode prior to writing out the actual code?

  1. Choose an everyday activity
  2. Imagine that you are providing instructions for this activity to a person who has never done it before
  3. Challenge someone to do the steps you wrote out

Ex. Brushing Teeth

  1. Pick up your toothbrush
  2. Rinse toothbrush
  3. Pick up toothpaste
  4. Place toothpaste on the toothbrush
  5. Rinse toothbrush again
  6. Brush teeth in a circular motion
  7. Spit
  8. Wash mouth
  9. Rinse toothbrush
  10. You have brushed your teeth!

Substring/Length Practice: change the print functions to print "hello", "bye", and the string length 

#the substring will have the characters including the index "start" to the character BEFORE the index "end"
#len(string) will print the length of string

string = "hellobye"
x = string[0:8]
y = string[0:5]
z = string[5:8]
print(x)
print(len(string))
print(y)
print(z)

hellobye
8
hello
bye

Concatenation Practice: combine string1 and string2 to make string3, then print string3.

string1 = "computer"
string2 = "science"
string3 = string1 + " " + string2
print(string3)

computer science

Homework/List Adaptation: create a function that prints the name of each string in the list and the string's length. Challenge: add frontend with javascript or html.

names = ["jaden","max","dylan","orlando"]

def length(list):
    for x in names: #calls the strings in the list of names
        print(x + " = " + str(len(x))) #prints the output "name" = the length (int) converted into a string
        
length(names)

jaden = 5
max = 3
dylan = 5
orlando = 7

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