Java - Help converting inches to cm, and weight to kg

Question

I'm doing a Java exercise, and I need to display a persons height in both inches and cm, as well as their weight in both pounds and kg.. Here's what I came up with, but I'm getting tons of errors.

Height = 74; // inches
Weight = 180; // pounds

System.out.println( "He's " + Height + " inches or + (Height * 2.54) cm tall "." );

I got the 2.54 by just googling what the conversion was for inches to cm. I basically did the same thing for the weight (see below)

System.out.println( "He's " + Weight + " pounds or + (Weight * 2.20) kg heavy "." ); 

My goal is to get it to display:

He's 74 inches (or 187.96 cm) tall. 
He's 180 pounds (or 81.6466266 kg) heavy.

Any help would be great, and sorry for such a basic question!

Answer 1

There are a couple of glaring syntax errors here:

System.out.println( "He's " + Height + " inches or + (Height * 2.54) cm tall "." );

Notice how the syntax highlighting on this page points them out. (Your IDE really should be doing that too.) You close a string at the end, then have a random . character and open another string which you never close.

You can fix the syntax errors by removing a quote:

System.out.println( "He's " + Height + " inches or + (Height * 2.54) cm tall ." );

However, this doesn't yet give you the output you want. Because this is just a string:

" inches or + (Height * 2.54) cm tall ."

Java isn't going to perform that calculation, as far as Java is concerned this is just text. You need to separate the string just like you already are for your other use of the variable:

System.out.println( "He's " + Height + " inches or " + (Height * 2.54) + " cm tall." );

Answer 2

You're writing text instead of a variable's value:

System.out.println( "He's " + Height + " inches or + (Height * 2.54) cm tall "." );

Change it to:

System.out.println( "He's " + Height + " inches or (" + (Height * 2.54) + " cm) tall.");

The same goes for the weight line:

System.out.println( "He's " + Weight + " pounds or + (Weight * 2.20) kg heavy "." );

Should be:

System.out.println( "He's " + Weight + " pounds or (" + (Weight * 2.20) + " kg) heavy."); 

And please follow Java naming conventions:

Except for variables, all instance, class, and class constants are in mixed case with a lowercase first letter. Internal words start with capital letters. Variable names should not start with underscore _ or dollar sign $ characters, even though both are allowed.

From the above: variable names should start with a lower case

You should also read How to concatenate characters in Java

Answer 3

This might answer your question, it is a bit vague, so I am mostly guessing.

System.out.println( "He's " + Height + " inches or (" + Height * 2.54 + ") cm tall." );

You had formatted your println pretty badly. It is the same for the later one, I suggest having a look at it and figuring that one out by yourself.

Also I have no clue of what unit of measurement you are using for your Weight and Height, I recommend a double for this scenario. If you want more precision you have to look up on BigDecimal.

Normally variables and fields are written in lowerCamelCase in Java.

Answer 4

System.out.println( "He's " + Height + " inches or ("+ (Height * 2.54)+" ) cm tall." );

Remember that you must do the conversion (without Strings quotes) before concatenate with text. The final dot is not needed.

Answer 5

First off, you need to define what datatype your variables are. You can't have "Height", you need to have "int Height".

It's also easier if you set variables for both height and weight in their respective units. So you should have a variable for height in inches, and then a variable for height in centimeters.

Here's my solution:

public static void main(String[] args) {
    int inHeight = 74;
    double cmHeight = inHeight * 2.54;
    int lbWeight = 180;
    double kgWeight = lbWeight / 2.2;

    System.out.println("He's " + inHeight + " inches (or " + cmHeight + " cm) tall.");
    System.out.println("He's " + lbWeight + " pounds (or " + kgWeight + " kg) heavy.");

}

Note: two of the variables are doubles, so if you want to correctly format those to two decimal places, you'll have to use "printf" instead of "println".

Answer 6

try this:

System.out.println( "He's " + Height + " inches or " + (Height * 2.54) + " cm tall "." );

Answer 7

Double Height = 74D; // inches
Double Weight = 180D; // pounds

System.out.println( "He's " + Height + " inches or " + (Height * 2.54)  + " cm tall "." );
System.out.println( "He's " + Weight + " pounds or " + (Weight * 2.20) + " kg heavy "." );