This question already has answers here:
ruby floating point errors
(3 answers)
Closed 7 years ago.
30.0 * 0.009 # => 0.26999999999999996
Does anybody know why this is not 0.27?
Any recommendations on what to do about this?
Since you already found materials on the why subject, I will just answer the what to do part of the question. If you absolutely don't want to approximate, you have to use rational numbers:
30 * 0.009r # => (27/100)
Related
This question already has answers here:
Java mapToInt vs Reduce with map
(2 answers)
Is there any advantage of calling map after mapToInt, where ever required
(3 answers)
Closed 3 years ago.
Following streams produces the same result however there are two different ways to achieve this.
Person.stream().map(Person::getAge).reduce(Integer::sum).get();
Person.stream().mapToInt( Person::getAge).sum();
I want to know difference among two and which one is better.
This question already has answers here:
How do I pick randomly from an array?
(7 answers)
Closed 8 years ago.
I am trying to understand how to use rand to do this. if there were two players for example player a and player b and the computer had to be one and the human the other. How would i implement this?
[:computer, :player].shuffle.first will give you on random who is first.
This question already has answers here:
Floating point error in representation?
(2 answers)
Closed 9 years ago.
Regarding multiplication, behavior of ruby is that 24.0 * 0.1 is not 2.4. Why does this happen?
24.0 * 0.1
# => 2.4000000000000004
Only very few numbers can be represented precisely in floating point arithmetic.
See http://en.wikipedia.org/wiki/Floating_point for more details.
This question already has answers here:
Classification score: SVM
(2 answers)
Closed 8 years ago.
I am using libsvm python interface and wondering is there a way to get a confidence score/probability when using multi-classification
I'd recommend the scikit-learn wrapper of libSVM which incoroporates a predict_proba function and a score function http://scikit-learn.org/stable/modules/generated/sklearn.svm.SVC.html#sklearn.svm.SVC.
This question already has an answer here:
Difference between String.scan and String.split
(1 answer)
Closed 9 years ago.
What is the difference between ".scan" and ".split" in Ruby language?
Can someone give me an example?
i am really got confused about it!
scan extracts substrings that match the given regex.
split extracts substrings that do not match the given regex (and optionally, substrings that match as well).