Using OF Function in a Function

Just like any regular call

void ofApp::draw() {
    float dist = distance(n, valx, valy);
}

float ofApp::distance(int n,int valX, int valY){
    float d;
    d = sqrt((valY-mouseY)*(valY-mouseY)+(valX-mouseX)(valX-mouseX));
    return d;
}