Basic calculations

Mathematical operations

Here is a list of all the mathematical operations that Eudox can handle.

 + Addition - Subtraction * Multiplication / Division ^ Power

Calculate simple expressions

To calculate an expression you just type in the expression and press Enter. For example if you would like to calculate 1+2 you type: '1' '+' '2' and hit the enter key. You will now see two new lines in the result field. The first line where the blue arrow is tells you what you typed in. The second line tells you the result of the expression.

Here are some examples of simple expressions that Eudox will calculate for you. Remember that Eudox use '.' for a decimal point, not ',' which would be more common in Sweden and some other countries.

You can use the last result given by Eudox by type % like this. Eudox will answer 16 because that was the last result it gave you (2^(1+3)).
You can also use % in expressions. Mathematical constants Here is a list of mathematical constants that Eudox can handle.

 p Pi e e (base of natural logarithms)

This calculates some expressions with mathematical constants. Remember to be careful with mathematical constants so you do not mix them with variables. For example, you can't use e or p as a variable in the plot functions.

Mathematical functions

Eudox can handle a lot of functions. In Eudox we separate functions and commands, functions have parentheses ("(...)") around its argument and commands have square brackets ("[...]") Here is a list of all the mathematical functions that Eudox can handle.

 sin( expr ) Calculate the sine for expr cos( expr ) Calculate the cosine for expr tan( expr ) Calculate the tangent for expr asin( expr ) Calculate the arcsine for expr acos( expr ) Calculate the arccosine for expr atan( expr ) Calculate the arctangent for expr abs( expr ) Calculate the absolute value for expr ln( expr ) Calculate the natural logarithm for expr lg( expr ) Calculate the logarithm of base 10 for expr sqrt( expr ) Calculate the square root for expr

To calculate for example cos(0) just type it in and press enter. Eudox will use radians if nothing else is specified.
Here are some calculations with mathematical functions.  Here are some mathematical functions with IsRad=0 specified. Variables

Eudox can handle variables that can contain values, expressions or data. To create a variable use the function NewVariable[]

 Syntax: NewVariable[name, value]

This creates a variable named temp and stores the value zero in it. Remember that you can't create variables that have the same name as a constant or function. We also strongly recommend that you do not use x, y, z or t because they are often associated with plotting.
When you have defined a variable, you can use it in all kinds of expressions. It is possible to change the value for a variable after it has been defined. This sets the value 3.7 to the already defined variable u. There are many variables defined already from the start. These variables determine how various parts of Eudox will work.
To list all variables in Eudox use the command ListVariables[]
Later on in this book, we will discuss what these variables do.

Commands

Eudox has lots of commands to process and visualize all kinds of values, expressions and data. Commands differ from functions by the square brackets and that all command must have the first letter uppercased.

You can also create your own functions. But your "custom made" function have to use the square brackets instead of parentheses. This is because functions with parentheses are reserved for predefined Eudox functions. This will improve speed. Creating a function is similar to creating a variable. You use the command NewFunction[]

 Syntax: NewFunction[name, function]

This create a function and store the sin(x)+cos(x) in it. This calculates the function with p/2 as the x value. This sets the expression for R after is has been created. Eudox contains about 40 commands to create, calculate and visualize values, expression and data. All of these functions will be explained in this book.

Help

 Syntax: Help[ function or variable]

You can use Help[] to get the syntax and an example of a command. This tell you how to use Plot[] (The function Plot will be covered later in this book) Next: Numerical and symbolix commands