Help for EZ Graph
How to enter functions, possibly with variables.
How to set x- and y-axes bounds.
How to trace x, y coordinate pairs for functions.
How to set angle units for trigonometry functions.
Basically, you type a function into the 'y =' field, select the 'Use' choice, press the 'Draw Graph' button, and the graph of that function is drawn.
For example, if you type '2 * x + 4' (no quotes) into the top 'y =' field, select the 'Use 1' choice, and press the 'Draw Graph' button, a straight line graph with a slope of 2 and a y-intercept of 4 will be drawn.
The function expression that you enter should have an x variable in it.
The following arithmetic operations work with EZ Graph:
| + | Means addition, as in 3 + 5 evaluates to 8. |
| - | Means subtraction, as in 8 - 2 evaluates to 6. |
| * | Means multiplication, as in 3 * 5 evaluates to 15. |
| / | Means division, as in 8 / 2 evaluates to 4. |
| ^ | Means raise to a power, as in 3 ^ 2 evaluates to 9. |
| + | Also means positive, as in +5 evaluates to positive 5. |
| - | Also means negative, as in -8 evaluates to negative 8. |
The order of arithmetic operations proceeds as follows:
| ( ) | Parentheses, highest precedence, can be nested. |
| ^ | Raise to power, next precedence, proceeds left to right. |
| + and - | Plus and minus sigh, next precedence, proceeds right to left. |
| * and / | Multiplication and division, next precedence, proceeds left to right. |
| + and - | Addition and subtraction, final precedence, proceeds left to right. |
So, for example, 4 + 2 * -3 ^ 2 evaluates to -14.
EZ Graph supports parentheses.
For example, (2 + 5) * 3 evaluates to 21.
Common trigonometric functions are supported by EZ Graph. These functions include the sine, cosine, tangent, arcsine, arcosine, and arctangent.
The trigonometric functions will work with angles measured either in degrees or radians. This choice is made by selecting the 'Degrees' or 'Radians' button.
Assuming that 'Degrees' is selected, this is the meaning of the following trigonometric functions:
| sin(30) | Means the sine of 30 degrees. |
| cos(60) | Means the cosine of 60 degrees. |
| tan(45) | Means the tangent of 45 degrees. |
| asin(0.5) | Means the arcsine of 0.5, returned in degrees. |
| acos(0.7071) | Means the arccosine of 0.7071, returned in degrees. |
| atan(1.0) | Means the arctangent of 1.0, returned in degrees. |
If 'Radians' is selected instead of 'Degrees', then the sine, cosine, and tangent functions would accept radian angle measurements, and the arcsine, arccosine, and arctangent functions would return angles measured in radians.
Exponential and logarithmic functions are supported by EZ Graph.
Here are some descriptive examples:
| exp(3) | Means e raised to the power of 3. |
| ln(20) | Means the natural logarithm of 20. |
| log(30) | Means the logarithm to base 10 of 30. |
The square root of a number works this way in EZ Graph:
| sqrt(3) | Means the square root of 3. |
These operations and functions may be combined freely. For example:
sin(cos(ln(2 + 3^4))) * 3^2 * 3 + sqrt(cos(-45))
If you type in something incorrectly, such as ton(30) instead of tan(30), an error message will appear on the graph. This message will include the part of the expression where the error occurred.
Sometimes a semicolon will be indicated as the part of the function where the error occurred, even though a semicolon does not appear in your function. This just means that the error occurred at the very end of your function.