fn main() { // basic arithmetic assert_eq!(6.0_f32*6.0_f32, 36.0_f32); assert_eq!(6.0_f64*6.0_f64, 36.0_f64); assert_eq!(-{5.0_f32}, -5.0_f32); assert_eq!(-{5.0_f64}, -5.0_f64); // infinities, NaN assert!((5.0_f32/0.0).is_infinite()); assert!((5.0_f64/0.0).is_infinite()); assert!((-5.0_f32).sqrt().is_nan()); assert!((-5.0_f64).sqrt().is_nan()); // byte-level transmute let x: u64 = unsafe { std::mem::transmute(42.0_f64) }; let y: f64 = unsafe { std::mem::transmute(x) }; assert_eq!(y, 42.0_f64); let x: u32 = unsafe { std::mem::transmute(42.0_f32) }; let y: f32 = unsafe { std::mem::transmute(x) }; assert_eq!(y, 42.0_f32); // f32-to-int casts assert_eq!(5.0f32 as u32, 5); assert_eq!(-5.0f32 as u32, 0); assert_eq!(5.0f32 as i32, 5); assert_eq!(-5.0f32 as i32, -5); assert_eq!(std::f32::MAX as i32, i32::MAX); assert_eq!(std::f32::INFINITY as i32, i32::MAX); assert_eq!(std::f32::MAX as u32, u32::MAX); assert_eq!(std::f32::INFINITY as u32, u32::MAX); assert_eq!(std::f32::MIN as i32, i32::MIN); assert_eq!(std::f32::NEG_INFINITY as i32, i32::MIN); assert_eq!(std::f32::MIN as u32, 0); assert_eq!(std::f32::NEG_INFINITY as u32, 0); assert_eq!(std::f32::NAN as i32, 0); assert_eq!(std::f32::NAN as u32, 0); assert_eq!(u128::MAX as f32, std::f32::INFINITY); assert_eq!((u32::MAX-127) as f32 as u32, u32::MAX); // rounding loss assert_eq!((u32::MAX-128) as f32 as u32, u32::MAX-255); // rounding loss // f64-to-int casts assert_eq!(5.0f64 as u64, 5); assert_eq!(-5.0f64 as u64, 0); assert_eq!(5.0f64 as i64, 5); assert_eq!(-5.0f64 as i64, -5); assert_eq!(std::f64::MAX as i64, i64::MAX); assert_eq!(std::f64::INFINITY as i64, i64::MAX); assert_eq!(std::f64::MAX as u64, u64::MAX); assert_eq!(std::f64::INFINITY as u64, u64::MAX); assert_eq!(std::f64::MIN as i64, i64::MIN); assert_eq!(std::f64::NEG_INFINITY as i64, i64::MIN); assert_eq!(std::f64::MIN as u64, 0); assert_eq!(std::f64::NEG_INFINITY as u64, 0); assert_eq!(std::f64::NAN as i64, 0); assert_eq!(std::f64::NAN as u64, 0); assert_eq!(u128::MAX as f64 as u128, u128::MAX); assert_eq!((u64::MAX-1023) as f64 as u64, u64::MAX); // rounding loss assert_eq!((u64::MAX-1024) as f64 as u64, u64::MAX-2047); // rounding loss // f32 <-> f64 casts assert_eq!(5.0f64 as f32, 5.0f32); assert_eq!(5.0f32 as f64, 5.0f64); assert_eq!(std::f64::MAX as f32, std::f32::INFINITY); assert_eq!(std::f64::MIN as f32, std::f32::NEG_INFINITY); assert_eq!(std::f32::INFINITY as f64, std::f64::INFINITY); assert_eq!(std::f32::NEG_INFINITY as f64, std::f64::NEG_INFINITY); // f32 min/max assert_eq!((1.0 as f32).max(-1.0), 1.0); assert_eq!((1.0 as f32).min(-1.0), -1.0); assert_eq!(std::f32::NAN.min(9.0), 9.0); assert_eq!(std::f32::NAN.max(-9.0), -9.0); assert_eq!((9.0 as f32).min(std::f32::NAN), 9.0); assert_eq!((-9.0 as f32).max(std::f32::NAN), -9.0); // f64 min/max assert_eq!((1.0 as f64).max(-1.0), 1.0); assert_eq!((1.0 as f64).min(-1.0), -1.0); assert_eq!(std::f64::NAN.min(9.0), 9.0); assert_eq!(std::f64::NAN.max(-9.0), -9.0); assert_eq!((9.0 as f64).min(std::f64::NAN), 9.0); assert_eq!((-9.0 as f64).max(std::f64::NAN), -9.0); // f32 copysign assert_eq!(3.5_f32.copysign(0.42), 3.5_f32); assert_eq!(3.5_f32.copysign(-0.42), -3.5_f32); assert_eq!((-3.5_f32).copysign(0.42), 3.5_f32); assert_eq!((-3.5_f32).copysign(-0.42), -3.5_f32); assert!(std::f32::NAN.copysign(1.0).is_nan()); // f64 copysign assert_eq!(3.5_f64.copysign(0.42), 3.5_f64); assert_eq!(3.5_f64.copysign(-0.42), -3.5_f64); assert_eq!((-3.5_f64).copysign(0.42), 3.5_f64); assert_eq!((-3.5_f64).copysign(-0.42), -3.5_f64); assert!(std::f64::NAN.copysign(1.0).is_nan()); }