## How can I have matlab identify if a specific element is repeated a specific number of times?

### George (view profile)

on 12 Dec 2012

Lets say a I have a 10 by 10 matrix with a random combination of numbers. So I want MATLAB to check a specific number is repeated a specific times. For example, what can I type if I want MATLAB to check if the number 1 is repeated 3 times in the 10 by 10 matrix?

## Products

### Walter Roberson (view profile)

on 12 Dec 2012

```sum(A(:) == 1) == 3
```

George

### George (view profile)

on 13 Dec 2012

So if I would like to see if the number 2 is in the matrix 3 times would I type

sum(A(:)==2)==3

Walter Roberson

### Walter Roberson (view profile)

on 13 Dec 2012

Yes,

```sum(A(:) == NumberToTestFor) == CountRequired
```

### Muruganandham Subramanian (view profile)

on 12 Dec 2012
Edited by Muruganandham Subramanian

### Muruganandham Subramanian (view profile)

on 12 Dec 2012

try this:

` find(A==1)`

If you would like to know more,

```>>help find
```

Walter Roberson

### Walter Roberson (view profile)

on 12 Dec 2012

That does not check to see if the element was repeated the correct number of times.

Muruganandham Subramanian

### Muruganandham Subramanian (view profile)

on 12 Dec 2012

If you need to check for no.of times, assign a variable

```   c=find(A==1)
size(c)```
Walter Roberson

### Walter Roberson (view profile)

on 12 Dec 2012

You can apply size() to an expression

```size(find(A==1))
```

size() is, either way, going to return a vector of dimensions. Which of those elements should George check? Will the answer vary in newer MATLAB versions which are changing the rules about whether various functions return row outputs or column outputs?

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