ofRandom * float variable?

beginners
#1

I’m trying to control the amount of randomness with a global variable but I get weird results.

Basically I’m declaring a float at the top of my code and using it in testApp::update to be multiplied with ofRandom:

  
float rectRand = 100;  
  
cout << ofRandom(1) * 100 << endl;

I get extremely small numbers:

1.26117e-44
8.40779e-45
1.68156e-44
5.60519e-45
2.8026e-45
1.4013e-45
4.2039e-45
5.60519e-45
2.8026e-45
1.54143e-44
1.12104e-44
1.4013e-44
7.00649e-45
8.40779e-45
1.54143e-44
5.60519e-45
0
1.12104e-44
2.8026e-45

And whenever I’m using an int instead of float (int rectRand = 100) I seem to get only values between 0 and 13:

4.43989
2.45417
5.47276
11.19
12.3605
6.39323
3.79754
2.10299
6.60152
4.9348
2.72991
5.49871
3.03373

What am I missing here?

#2

Apparently I had to make the variable a double.

Any suggestions why?

#3

hm, this is really weird, but I can’t reproduce it.
This in emptyExample update() function:

  
    float myFloat = 100.0;  
    int myInt = 100;  
    double myDouble = 100.0;  
    ofLog(OF_LOG_NOTICE, "Int: %g, Float: %g, double: %g", ofRandom(1) * myInt, ofRandom(1) * myFloat, ofRandom(1) * myDouble);

gives, as expected:

  
[notice] Int: 42.8355, Float: 16.327, double: 12.994  
[notice] Int: 28.4969, Float: 4.48999, double: 47.831  
[notice] Int: 54.7669, Float: 69.9344, double: 16.6802  
[notice] Int: 42.5372, Float: 97.0982, double: 19.3167  
[notice] Int: 35.294, Float: 92.8939, double: 35.7759  
[notice] Int: 96.4609, Float: 96.7863, double: 28.0223  
[notice] Int: 35.7959, Float: 38.8857, double: 65.8181  
[notice] Int: 55.5719, Float: 66.0126, double: 16.9108  
[notice] Int: 49.6267, Float: 40.8757, double: 9.09463  
[notice] Int: 27.476, Float: 58.2255, double: 5.75573  
[notice] Int: 43.803, Float: 71.2196, double: 83.8503  
[notice] Int: 48.293, Float: 19.0505, double: 26.6858
#4

Thanks for your reply!

You’re right. I was trying to set an index an with a bigger index than it’s size (array had size 2 and I was doing array[2]). That messed up everything. I wonder why though. I would have expected xcode not to compile in a case like this anyway.