Does JavaScript have double floating point number precision?
All numbers in JavaScript are 64-bit floating point numbers. Ref: http://www.hunlock.com/blogs/The_Complete_Javascript_Number_Reference http://www.crockford.com/javascript/survey.html
double-precision
How to correctly and standardly compare floats?
From The Floating-Point Guide: This is a bad way to do it because a fixed epsilon chosen because it “looks small” could actually be way too large when the numbers being compared are very small as well. The comparison would return “true” for numbers that are quite different. And when the numbers are very large, … Read more
strange output in comparison of float with float literal
This happens because in your statement if(f == 0.7) the 0.7 is treated as a double. Try 0.7f to ensure the value is treated as a float: if(f == 0.7f) But as Michael suggested in the comments below you should never test for exact equality of floating-point values.
Should I use double or float?
If you want to know the true answer, you should read What Every Computer Scientist Should Know About Floating-Point Arithmetic. In short, although double allows for higher precision in its representation, for certain calculations it would produce larger errors. The “right” choice is: use as much precision as you need but not more and choose … Read more
How do you round a double in Dart to a given degree of precision AFTER the decimal point?
See the docs for num.toStringAsFixed(). String toStringAsFixed(int fractionDigits) Returns a decimal-point string-representation of this. Converts this to a double before computing the string representation. If the absolute value of this is greater or equal to 10^21 then this methods returns an exponential representation computed by this.toStringAsExponential(). Examples: 1000000000000000000000.toStringAsExponential(3); // 1.000e+21 Otherwise the result is the … Read more