Project: a name card

What you will be able to do

After this lesson you can

• turn a picture on paper into a program of print() lines,
• repeat a character with text times a number,
• check your output against the plan, and
• change the program for another person.

The goal

We want a name card like this one:

+------------------------+
|  Name   : Asha         |
|  Class  : 7B           |
|  School : Green Hill   |
+------------------------+

It is only text, but it is a good first project, because every line has to be exactly right.

Step 1: plan on paper

Before you type, look at the card.

• It has 5 lines.
• The first and the last lines are the same: a plus sign, a row of dashes, and a plus sign.
• The three middle lines start and end with the sign |.
• Each line has the same width. Count the characters of the top line. Every other line must have the same number.

A plan like this saves time. It is easier to fix a plan than to fix a program.

Step 2: write it one line at a time

A beginner writes the whole program at once and cannot find the mistake. A programmer writes one or two lines, runs, looks, and goes on. Start with only the top line.

Step 3: repeat a character

Typing 24 dashes is slow, and you may count wrong. Python can repeat text for you: text times a number repeats the text.

The whole program is here.

A text times a negative number is empty. So when the name is too long, no spaces are added, and the line sticks out.

Step 4: check it

Look at the output and compare it with your plan. Check three things.

1. Are there 5 lines?
2. Do the plus signs and the bars | line up in one straight column on the right?
3. Is the information right?

If the right edge is crooked, one line has too few or too many spaces. Count the characters of that line.

Step 5: make it yours

A project is yours only when you change it. Do these, one at a time, and run after each one.

1. Put your own name, class and school in the card.
2. Change 24 to 30 in the border. Now the card is wider. What must you change in the other lines to keep it neat?
3. Add a fourth line, City.
4. Make a card for a friend, with a different border sign, such as * or =.

Common mistakes

• Lines of different widths. Count the characters. Use the same number of spaces in every line.
• Forgetting a quotation mark at the end of a line.
• Writing everything first and running at the end. Run after each line.
• Typing the border twice by hand. Use the repeat, so that one change fixes both lines.

Practice

Start with two quick questions. Each New numbers gives you a fresh one, so you can practise as long as you like.

Then the labs and the problems:

1. Warm-up. Open the lab Project: the name card. Write the program. The checker counts the lines and the width.
2. Build. Do Step 5 above.
3. Stretch. Draw a house or a robot with print(), like the lab A house made of text, and make the roof wider with a repeat.

Remember these

• Plan on paper first. Count lines and widths.
• Write a few lines, run, look, and go on.
• "-" * 24 repeats a character. Use it, instead of typing a character many times.
• Check the output against the plan.

Check yourself

Try each one on your own first. If you are stuck, open a hint. Then check with Show the answer.

1. What does "=" * 5 give?

2. Why do we build a program one or two lines at a time?

3. How can you check that all the lines of a card have the same width?