Adding 1 to a single element of a two dimensional array

Projects Programming
1

Hi

I would like to add 1 to a single element of a 2 dimensional array, for example if the declared array is:

uint8_t array1 [2][2] = {{1,2},{3,4}};

and at some point in the main loop I want to add 1 to element [2][2]. How do I do it?

I have tried:

array1 [2][2] = array1 [2][2]+1;
array1 [2][2] = {array1 [2][2]+1};
array1 [2][2] = {{array1 [2][2]}+1};
array1 [2][2] = {(array1 [2][2])+1};

Thanks

2 
array1 [2][2] =

A two element array doesn't have 2 as a valid subscript.

To add one to elements

array1 [0][0]++;
array1 [0][1]++;
array1 [1][0]++;
array1 [1][1]++;
3

Hi Sorry I just reread the question and as always I made some mistakes

2 dimensional array as in

uint8_t array1 [2][2] = {{1,2},{3,4}};

and adding one to element [2][2], so as to become:

uint8_t array1 [2][2] = {{1,2},{3,5}};

Understand what I mean?

Cheers
D

4 
array1 [1][1]++;
5

Hi,

I've tried it but.... it doesn't work :confused:

//uint8_t decimal_X [21] [2]; // This is how the array is defined
//uint8_t decimal_Y [21] [2];

decimal_X[0][0] = {1+1};
decimal_Y[0][0] = {9};

Serial.print("X&Y:\t");
Serial.print(decimal_X[0][0]);
Serial.print("\t");
Serial.println(decimal_Y[0][0]);

decimal_X[0][0]++;
decimal_Y[0][0]++;

and here is the output I get in attachment

Screen Shot 2017-02-19 at 20.25.01.png

6

it doesn't work

Lamest comment . . . ever.
The code you posted doesn't / cannot compile, so cannot "work".

If you want help, be specific.

7

You didn't think your "report to moderator" through, did you?

I'm the fat guy off the Simpsons.

8

Its from a larger section of code

uint8_t decimal_X [21] [2];
uint8_t decimal_Y [21] [2];

void setup() {
  Serial.begin(115200);
  while (!Serial);

  
}

void loop() {


decimal_X[0][0] = {1+1};
decimal_Y[0][0] = {9};

Serial.print("X&Y:\t");
Serial.print(decimal_X[0][0]);
Serial.print("\t");
Serial.println(decimal_Y[0][0]);

decimal_X[0][0]++;
decimal_Y[0][0]++;

}
9

OK, so what's your definition of "this code works"?
(please bear in mind the fact that you overwrite the values you just incremented each time through loop() )

10

Ow dear :o .... oops ;/ ouch .... cheery o fat guy from Simpsons :slight_smile: