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Math
This library allows for the calculation of min/max, absolute value and the square root of a number. Users can also constrain a number within a range, re-map a number from one range to another, and calculate the value of a number raised to a power.
min
- Description
- Calculates the minimum of two numbers.
- Syntax
- min(x, y)
- Parameters
- x: The first number, any data type
y: The second number, any data type - Returns
- The smaller of the two numbers.
max
- Description
- Calculates the maximum of two numbers.
- Syntax
- max(x, y)
- Parameters
- x: The first number, any data type
y: The second number, any data type - Returns
- The larger of the two parameter values.
abs
- Description
- Computes the absolute value of a number.
- Syntax
- abs(x)
- Parameters
- x: The number
- Returns
- If x is greater than or equal to 0. -x: If x is less than 0.
constrain
- Description
- Constrains a number to be within a range.
- Syntax
- constrain(x, a, b)
- Parameters
- x: The number to constrain, all data types
a: The lower end of the range, all data types
b: The upper end of the range, all data types - Returns
- x: If x is between a and b. a: If x is less than a. b: If x is greater than b.
map
- Description
- Re-maps a number from one range to another. That is, a value of fromLow would get mapped to toLow, a value of fromHigh to toHigh, values in-between to values in-between, etc.
- Syntax
- map(value, fromLow, fromHigh, toLow, toHigh)
- Parameters
- value: The number to map
fromLow: The lower bound of the value's current range
fromHigh: The upper bound of the value's current range
toLow: The lower bound of the value's target range
toHigh: The upper bound of the value's target range - Returns
- The mapped value.
pow
- Description
- Calculates the value of a number raised to a power.
- Syntax
- pow(base, exponent)
- Parameters
- base: The number (float)
exponent: The power to which the base is raised (float) - Returns
- The result of the exponentiation (double)
sqrt
- Description
- Calculates the square root of a number.
- Syntax
- sqrt(x)
- Parameters
- x: The number, any data type
- Returns
- Double, the number's square root.
Example
Output a calculation with constrain() and pow().
#include <Arduino.h>
void setup(){
Serial.begin(9600);
}
void loop(){
Serial.println("Caluculate the area of a circle ");
Serial.println("Input value 0-9");
while(!Serial.available());
int d = Serial.read();
d = constrain(d - 0x30, 0, 9); //convert from ASCII to numeric, and remove error value
Serial.print(d);
Serial.print(" x ");
Serial.print(d);
Serial.print(" x 3.14 = ");
Serial.println(pow(d, 2) * PI);
}