sqrtf

sqrtf is a function in the C standard library that computes the square root of a single-precision floating-point value. It operates on values of type float and returns a float. It is declared in the header math.h and serves as the single-precision counterpart to sqrt, which operates on double.

Declaration and signature: float sqrtf(float x);

Behavior and domain: For non-negative input x, sqrtf returns the principal (non-negative) square root. If x is NaN, the result is NaN. If x is negative (and not NaN), the function signals a domain error and typically returns NaN; some implementations may set errno to EDOM. The treatment of signed zero can vary by platform, but the result is non-negative for non-negative inputs.

Usage: Include the math library and link against it (usually with -lm on many systems). Example: float r = sqrtf(2.0f); This yields r approximately 1.4142135f. Because sqrtf returns a float, its precision is limited to single precision.

Notes and related functions: sqrtf is designed for single-precision math and is distinct from sqrt (double precision) and sqrtl (long double precision). In C++, the standard library provides std::sqrt with overloads for float, double, and long double, and some environments also expose sqrtf from the C headers. Performance may benefit from hardware-accelerated instructions on modern CPUs, and implementations may use optimized algorithms suitable for floats.

See also: sqrt, sqrtl, std::sqrt (in C++).