Should I use double or float?

by

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 the right algorithm.

Many compilers do extended floating point math in “non-strict” mode anyway (i.e. use a wider floating point type available in hardware, e.g. 80-bits and 128-bits floating), this should be taken into account as well. In practice, you can hardly see any difference in speed — they are natives to hardware anyway.

More Related Contents:

  1. strange output in comparison of float with float literal
  2. C++ decimal data types
  3. How to correctly and standardly compare floats?
  4. c++ Making a code that displays equations and keep getting the “expression must have integral or unscoped enum type” error
  5. Size of character (‘a’) in C/C++
  6. Why does changing 0.1f to 0 slow down performance by 10x?
  7. When should I use double instead of decimal?
  8. Finding the type of an object in C++
  9. Difference between string and char[] types in C++
  10. When to use bit-fields in C?
  11. When is uint8_t ≠ unsigned char?
  12. Why does printf() promote a float to a double?
  13. C++ floating point precision [duplicate]
  14. “X does not name a type” error in C++
  15. Floating point format for std::ostream
  16. Convert float to string with precision & number of decimal digits specified?
  17. double or float, which is faster? [duplicate]
  18. Why does long long n = 2000*2000*2000*2000; overflow?
  19. Change floating point rounding mode
  20. Emulate “double” using 2 “float”s
  21. C++: How to round a double to an int? [duplicate]
  22. Floating point Endianness?
  23. Stopping the debugger when a NaN floating point number is produced
  24. Is it possible to create a type in c++ that takes less than one byte of memory?
  25. Cast to int vs floor
  26. C++ string literal data type storage
  27. Matlab vs C++ Double Precision
  28. Is there a functional difference between “2.00” and “2.00f”?
  29. C++ Class wrapper around fundamental types
  30. Why isn’t “0f” treated as a floating point literal in C++?

Leave a Comment