[CWM] Simple Operations

Overview of Code with Me Video Lectures

• Focus on problem-solving and coding collaboratively in class.

• Aim to integrate various topics learned throughout the course.

Creating and Organizing Code Files

• Introduction to creating a JavaScript (JS) file using Notepad++.

• Emphasis on file organization:

  • Suggestion to create a dedicated folder for code (e.g., "dev" located in the root of the C drive).

• Saving files for syntax highlighting; comments convert to green indicating proper syntax.

First Problem: Calculating Distance Traveled by a Car

• Problem statement setup:

  • Task: Write a program that calculates the distance a car travels based on its speed.

  • Given values: Speed of the car = 70 miles per hour.

• Distance Calculation Formula:

  • Formula: $\text{Distance} = \text{Speed} \times \text{Time}$.

• Problem requirements:

  • Inputs: Speed (70 mph), Time (6 hours, 10 hours, and 15 hours).

  • Outputs: Display distances for 6 hours, 10 hours, and 15 hours.

Breakdown of Solution Process

1. Define inputs and respective variables:

   • var carSpeed = 70;

2. Initialize distance variables for each time duration:

   • For 6 hours: var distanceAtSix = carSpeed * 6;

   • For 10 hours: var distanceAtTen = carSpeed * 10;

   • For 15 hours: var distanceAtFifteen = carSpeed * 15;

3. Display results using console.log:

   • Formatted output for clarity:
     console.log("The distance after 6 hours is: " + distanceAtSix); console.log("The distance after 10 hours is: " + distanceAtTen); console.log("The distance after 15 hours is: " + distanceAtFifteen);

4. Demonstrated method of running the code in the command prompt:

   • Access command prompt:

     • Start Menu → Search → Type "cmd."

   • Change directories to the working folder (dev):

     • Command: cd C:\dev\JS

   • Run the program using Node:

     • Command: node personal_info.js;

   • Outputs displayed for each distance calculation.

Second Problem: Calculating Miles Per Gallon (MPG)

• Problem outline:

  • Task: Calculate a car's miles per gallon based on distances driven and gallons used.

  • Given data: Driven = 100 miles; Gallons used = 7.

• MPG Calculation Formula:

  • Formula: $\text{MPG} = \frac{\text{Miles Driven}}{\text{Gallons Used}}$

  • Example: For 100 miles and 7 gallons: MPG = 100 / 7.

Setup of Variables and Outputs

1. Define inputs as variables:

   • var milesDriven = 100;

   • var gallonsUsed = 7;

2. Calculate MPG:

   • var mpg = milesDriven / gallonsUsed;

3. Display MPG value:

   • Example output with console.log:
     console.log("Miles per gallon is: " + mpg);

4. Introduction of rounding or truncating results:

   • Reference to previous lectures on using the Math object for rounding.

   • Consideration of rounding functions for specific formatting:

     • Math.floor(mpg) for rounding down to an integer.

     • Rounding for two decimal places must be revisited.

Conclusion

• Encouragement to explore practical coding applications through these exercises.

• Highlight on the necessity of clear understanding of distance and MPG calculations in programming.

• Invitation to revisit topics in future videos for further clarity on JavaScript topics and coding techniques.