Cheatography

# Computer Language - Unit 4 - Selections Cheat Sheet (DRAFT) by papapadzul

Python - Computer Language

This is a draft cheat sheet. It is a work in progress and is not finished yet.

### Comparison Operators

 radius = 4 Python Operator Name Example Result < less than radius < 0 FALSE <= less than or equal to radius <= 0 FALSE > greater than radius > 0 TRUE >= greater than or equal to radius >= 0 TRUE == equal to radius == 0 FALSE != not equal to radius != 0 TRUE

### Generating Random Numbers

 ``````randint(a, b) # random int between a and b 1 import random 2 3 # Generate random numbers 4 5 number2 = random.randint(0, 9) 6 7 # Prompt the user to enter an answer 8 answer = eval(input("What is "+ + " + " 9 + str(number2) + "? ")) 10 11 # Display result 12 print(number1, "+", number2, "=", answer, 13 "is", number1 + number2 == answer)``````

### If statements

 One-way If statements A one-way if statement executes the statements if the condition is true. Two-Way if-else Statements A two-way if-else statem­ent.A two-way if-else statement decides which statements to execute based on whether the condition is true or false. Nested if and Multi-Way if-eli­f-else Statements One if statement can be placed inside another if statement to form a nested if statement.

### Logical Operators

 Operator Descri­ption not logical negation and logical conjun­ction or logical disjun­ction

### Operator Precedence Chart

 +, - (Unary plus and minus) ** (Expon­ent­iation) not *, /, //, % (Multi­pli­cation, division, integer division, and remainder) +, - (Binary addition and subtra­ction) <, <=, >, >= (Compa­rison) ==, != (Equality) and or =, +=, -=, *=, /=, //=, %= (Assig­nment operators)

### one-way if

 ``````1 number = eval(input("Enter an integer: ")) 2 3 if : 4 print("HiFive") 5 6 if : 7 print("HiEven")``````

### two-way if-else

 ``````1 import random 2 3 # 1. Generate two random single-digit integers 4 number1 = random.randint(0, 9) 5 number2 = random.randint(0, 9) 6 7 # 2. If number1 < number2, swap number1 with number2 8 if number1 < number2: 9 number1, number2 = number2, number1 # Simultaneous assignment 10 11 # 3. Prompt the student to answer "What is number1 - number2?" 12 answer = eval(input("What is "+ str(number1) + " - " + 13 str(number2) + "? ")) 14 15 # 4. Check the answer and display the result 16 if number1 - number2 == answer: 17 print("You are correct!") 18 else: 19 print("Your answer is wrong.\n", number1, '-', 20 number2, "is", number1 - number2, '.')``````

### Nested if and Multi-Way if-eli­f-else

 ``````1 year = eval(input("Enter a year: ")) 2 zodiacYear = year % 12 3 if zodiacYear == 0: 4 print("monkey") 5 elif zodiacYear == 1: 6 print("rooster") 7 elif zodiacYear == 2: 8 print("lion") 9 elif zodiacYear == 3: 10 print("goat") 11 elif zodiacYear == 4: 12 print("rat") 13 elif zodiacYear == 5: 14 print("ox") 15 elif zodiacYear == 6: 16 print("tiger") 17 elif zodiacYear == 7: 18 print("rabbit") 19 elif zodiacYear == 8: 20 print("dragon") 21 elif zodiacYear == 9: 22 print("snake") 23 elif zodiacYear == 10: 24 print("horse") 25 else: 26 print("sheep")``````

### Comput­eBMI.py

 ``````1 # Prompt the user to enter weight in pounds 2 weight = eval(input("Enter weight in pounds: ")) 3 4 # Prompt the user to enter height in inches 5 height = eval(input("Enter height in inches: ")) 6 7 KILOGRAMS_PER_POUND = 0.45359237 # Constant 8 METERS_PER_INCH = 0.0254 # Constant 9 10 # Compute BMI 11 weightInKilograms = weight * KILOGRAMS_PER_POUND 12 heightInMeters = height * METERS_PER_INCH 13 bmi = weightInKilograms / (heightInMeters * heightInMeters) 14 15 # Display result 16 print("BMI is", format(bmi, ".2f")) 17 if bmi < 18.5: 18 print("Underweight") 19 elif bmi < 25: 20 print("Normal") 21 elif bmi < 30: 22 print("Overweight") 23 else: 24 print("Obese")``````

### LeapYe­ar.py

 ``````1 year = eval(input("Enter a year: ")) 2 3 # Check if the year is a leap year 4 isLeapYear = 5 6 7 # Display the result 8 print(year, "is a leap year?", isLeapYear)``````