Week 02 (63)

63

Floating Point Numbers

Floating point numbers model a (tiny) subset of ℝ

many real values don't have exact representation (e.g. 1/3)
numbers close to zero have higher precision (more accurate)

C has two floating point types

float ... typically 32-bit quantity (lower precision, narrower range)
double ... typically 64-bit quantity (higher precision, wider range)

Literal floating point values: 3.14159, 1.0/3, 1.0e-9

printf("%10.4lf", (double)2.718281828459);
displays ⎵⎵⎵⎵2.7183
printf("%20.20lf", (double)4.0/7);
displays 0.57142857142857139685