Ruby String To Integer Or Float

Converting strings to numbers ruby provides the to i and to f methods to convert strings to numbers.

Ruby string to integer or float.

To i will convert the string to an integer. Returns the smallest number greater than or equal to int with a precision of ndigits decimal digits default. Ceil ndigits integer or float click to toggle source. If you re converting strings to numbers and need error checking consider using float str or integer str.

This method returns a string that contains a representation of self as well as a fixed or exponential form of numbering. To i converts a string to an integer and to f converts a string to a float. In ruby float class is a subclass of numeric class. Usually defaults to 2 2250738585072014e 308.

If the platform supports denormalized numbers there are numbers between zero and float min. To f will convert the string to an float a floating pont. 0 0 next float returns the smallest positive floating point number including denormalized numbers. Let s start by taking a look at the class hierarchy of all the number related classes in ruby.

Example 123 50 to f 123 5 float 123 50 123 5 however there is a difference when the string is not a valid float. The smallest positive normalized number in a double precision floating point. String click to toggle source. Both of these will throw an exception if str is not a valid float integer.

Posted 14 april 2011 in programming finally a technical article this one caused by a seemingly simple question on stack overflow asking how to test if string is a number. Casting to a float. The objects of the float class represents real numbers using the native architecture s double precision floating point representation. The string objects in ruby have several methods to convert the string object into a number.

How to check if a string is numeric. Numeric integer fixnum bignum float complex rational bigdecimal standard library as you can see the numeric class is the parent for all the number classes. Integer ruby 2 5 0. To c will convert the string to a complex number.

It turns out that it s not entirely that simple to answer and there are lot of apparently correct ideas that all turn out to fail closer scrutiny.