cos

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Description

Calculates the cosine of an angle (in radians). The result will be between -1 and 1.

Note: for conversion degrees to radians, use rad2deg()

Inclusion

• defined in misc.h
• auto-loaded in main_general.h
• no #define required

Syntax

y = cos(a)

Parameters

• input:

  • a: The angle in Radians (float)

• output:

  • none

Returns

• The cosine of the angle (float).

Example Code

The below code prints a table for y=cos(x) between 0..360 degrees. Note that the example requires option #define USE_FTOA in file config.h for floating point output.

#include "main_general.h"
#include "uart1.h"
#include "putchar.h"

void setup() {

  float x,y;
  char  s1[20], s2[20];
  
  // init UART and printf()
  UART1_begin(115200);
  putcharAttach(UART1_write);
  
  // allow the terminal to launch
  sw_delay(1000);
  
  // print math table
  for (x=0.0; x<=360.0; x+=0.5) {
    y = cos(deg2rad(x));
    printf("%s  %s\n", floatToString(s1,x,2), floatToString(s2,y,2));
  }
  
}

void loop() {
  // dummy
}

Relevant Tutorial

• tbd

See also

• deg2rad()
• rad2deg()
• sin()
• tan()
• asin()
• acos()
• atan()
• atan2()