VTech Precomputer Power Pad Plus STRING VARIABLES, FIRST NUMBER, SECOND NUMBER, THE SUM IS, 10 PRINT 3000000*3000000

You will see the following on the screen:

FIRST NUMBER 8	press ENTER
SECOND NUMBER 15	press ENTER
THE SUM IS 23

Let’s take a look at the print statements on lines 50 through 70. The words in quotes are called a STRING or a LITERAL. Whatever you put between a set of quotation marks will appear on the screen exactly the way you typed it. Remember that quotation marks come in pairs!

Next, the semicolon tells the print statement to print what is immediately to the right of the end of the string. This is the number 8, which is the value in memory box A.

Suppose that you asked the computer to multiply 3 million times 3 million.

Let’s try. Type:

10 PRINT 3000000*3000000 press ENTER

RUN

The answer on the screen is 9E+12. This is the computer’s way of showing extremely large numbers. A number with the letter E and a number to the right of the decimal point is called scientific or exponential notation. You find the decimal point and move the number of places specified after the “E” to the right filling in with zeros. The long way to write out the above answer is 9,000,000,000,000. The procedure works in reverse for very small numbers. The number 9E-12 is .000000000009. This is a very small positive number. The number -9E+12 is a very large negative number while the number -9E-12 is a very small negative number.

STRING VARIABLES

String variables are similar to the numeric variables that we have been working with so far except that the variables contain alphabetic characters (numbers, letters and symbols). The name of the memory variable always contains a $ to distinguish it as a string variable. String variables are not used in arithmetic but allow you to store things like your pet’s name. Here are some examples:

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