expected primary-expression error

Projects Programming
1

Hi I'm trying to make a 4x4x4 LED Cube and there's a section of my code that maps a 2d array to 3d coordinates and I've been getting an error that says "expected primary-expression before 'aNum'"

the error refers to the line after //section D

here's my code

inline byte getLEDState(byte pattern[4][4][4], byte aNum, byte cNum)
{
 
  byte (aNum, cNum);
  // TODO: fill this in to return the value in the pattern array corresponding
  // to the anode (+) wire and cathode (-) wire number (aNum and cNum) provided.


//section A
  if (byte aNum <= 3 && byte cNum <= 3) {
  x = aNum;
  y = cNum;
  z = 1;
  }
  
//section B
 else if (byte aNum >= 4 && byte cNum <= 3) {
  x = aNum;
  y = cNum - 4;
  z = 2;
 }

//section C
else if (byte aNum <= 3 && byte cNum >= 4) {
  x = aNum;
  y = cNum - 4;
  z = 3;
  
}

//section D
else if ( byte aNum >= 4 && byte cNum >= 4) {
  x = aNum - 4;
  y = cNum - 4;
  z = 4;
  

}


}
 return 0; 

}
2 
else if ( byte aNum >= 4 && byte cNum >= 4) {

Why does that statement contain any type names? Declaring a new variable in an if conditional makes no sense.

The preceding if and else if statements are equally wrong. Fix them, and post again, if you still have problems.

3

ursulaott wrote (in part):

here's my code

when actually only a snippet of the code was provided.

This, too, is wrong:

byte (aNum, cNum);

There is a byte(...) function but I am only familiar with the one-argument version. Also, I would expect a function named byte to return a result, but any returned result is thrown away.

4

You don't need to (and can't) declare the type of aNum and cNum everywhere they are used.
Looks like a copy and paste error in Section B.
Looks like an extra '}' before the return statement.

inline byte getLEDState(byte pattern[4][4][4], byte aNum, byte cNum)
{
  // TODO: fill this in to return the value in the pattern array corresponding
  // to the anode (+) wire and cathode (-) wire number (aNum and cNum) provided.

  //section A
  if (aNum <= 3 && cNum <= 3) {
    x = aNum;
    y = cNum;
    z = 1;
  }

  //section B
  else if (aNum >= 4 && cNum <= 3) {
    x = aNum - 4;
    y = cNum;
    z = 2;
  }

  //section C
  else if (aNum <= 3 && cNum >= 4) {
    x = aNum;
    y = cNum - 4;
    z = 3;
  }

  //section D
  else if (aNum >= 4 && cNum >= 4) {
    x = aNum - 4;
    y = cNum - 4;
    z = 4;
  }
// }
return 0;
}