In this course we will see how to use mathematical functions in your program.In fact, it can be really useful to calculate the square root of a number, or having it’s absolute value.

Arithmetic operation

This is a list of basic operation:

Operator Code
Addition : + int addition =5 + 5 // Return 10 into the variable
Subtraction : – int subtracting =5 – 5 // Return 0 into the variable
Multiplication : * int multiplication = 7*2; // return 14 into the variable
Divison : / int division = 6/2; // return 3 in the variable
Modulo : % int modulo =7 % 5 // return 2 in the variable

Comparison operator

Operator Code
Is to not equal to : != if (5 !=8) { // Your code }; //Here we enter in the loop because 5 is different to 8.
Smaller than: < if (2<3) { // Your code }; // We enter in the loop because 2 is smaller than 3.
Smaller or equal to : <= if (2<=2) { // Your code }; //Here we enter in the loop because 2 is smaller or equal to 3.
Equal to : == if (6==6) { // Your code }; // Here we enter in the loop because 6 is equals to 6.
Bigger than : > if (9>1) { // Your code }; // Here we enter in the loop because 9 is bigger than 1
Bigger or equal to : >= if (9>=9) { // Your code }; // Here we enter in the loop because 9 is bigger or equal to 9.

Boolean operator

Opérateur Code
Logical NOT : ! if (!x) { //  if x is False Your code }
Logical AND : && if (5==5 && 2==2) { // The both conditions are true therefore we enter in the code. }
Logical OR : || if (3==3 || 4==4) { // We enter in this code because one of the two equalities is true. };

Absolute function: abs()

The function absolute value is used to be sure that a number is positive or null. This function can be also used to transform a negative number to a positive one.

The abs() function take in parameter a number positive or negative and return the same number in positive:

Here is an example with a negative number -5:
By taking 0, the function return 0:

Maximum function: max()

The maximum function take in parameters two numbers and return the biggest of the two :
Example between two numbers: x=23 and y=2 :

The function takes in parameter any type of variable: string, int, float...

The maximum function can be also used to have a minimum value!

In your program, you may need to retrieve a value of a sensor or have a minimum value in case if the value of the sensor is to low.

Here is an example:

In this example, the variable value_sensor take the value of the photoresistor if this the value is bigger than 20, otherwise it will take 20.

Minimum function: min()

The minimum function is the reverse of the maximum function, that ‘s mean that the function takes two values and return the smallest one.

Here is an example with the numbers : x=23, y=2:

The function return 2. X and Y can have a different type: string, int, float…

The maximum function can be also used to have a minimum value!

In a program, you can also need to retrieve a value from a sensor or a maximum value in case if the value of the sensor is too high.

Here is an example:

In this example, the variable value_sensor takes the value of the photoresistor if it’s lower than 20, otherwise it will take 20.

Square root function: sqrt()

The function sqrt is used to have the square root of a number:

The function sqrt() return a double.

Here is an example with the number 25:

Trigonometry : cosine, sine and tangent

We will see now how the cosine, sine and tangent works:

  • Cosine

The cosine function takes in parameter an angle in radian and return a value between 1 and -1:

The function takes in parameter a float and return a double.

Here is an example with the cosine with an angle of 90°:

  • Sine

The sine function takes in parameter an angle in radian and return a value between 1 to -1:

The function takes in parameter a float and return a double.

Here is an example with the sine with an angle of 90°:

  • Tangent

The function tangent takes in parameter an angle in radian and return a value between minus infinite to infinite:

  • Here is an example with the value 0: