Vtech Power Zone 2000 User Manual - Page 34

CALCULATOR This is an eight-digit, fully functional calculator for addition, subtraction, multiplication and division. You can move the pointer to click on the calculator buttons or use the keys from the keyboard to perform a calculation. The Calculator can be used to determine the answer to some of the questions in the Mathematics activities by pressing the Calculator icon. You can return to the activity by clicking the Return icon. Be sure to press the AC button to clear the Calculator before each calculation. LOGO This activity 'LOGO' lets you experience logo programming. You can learn more in other reference book. LOGO is a programming language that can be used to teach your PC to do some new things. One thing LOGO can teach your PC is how to draw pictures. This system of drawing is called Turtle Graphics. commands Instructions to the Turtle are called commands. Each command begins with a key word telling the Turtle what to do. For example, "forward" is a command that tells the Turtle to move forward; "right" is a command that tells the Turtle to turn to the "right." Often, commands will require additional information such as how far forward the Turtle should go. For example, "forward 30" tells the Turtle to move forward 30 steps; "right 90" is a command that tells the Turtle to turn 90 degrees (a quarter turn) to the right. If additional information is required for a command, it must appear immediately after the command and separated from the command by a space. In the home position, the Turtle, represented by a triangle, sits at the center of the screen pointing straight up. This location is indicated with the pair of numbers (0,0). The first number of this pair indicates how far left or right the Turtle is from the center of the screen; it is also called the x-coordinate. The second number indicates how far up or down the Turtle is from the center of the screen; it is also called the y-coordinate. For example, the pair (10, -5) indicates that the Turtle is 10 steps to the right and 5 steps below the center of the screen. routines Additional commands can be created by defining new LOGO routines. For example, here is a LOGO routine that could create a square: to square forward 30 right 90 forward 30 right 90 forward 30 right 90 forward 30 right 90 26