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Rust-round-f32-using-arithmetic-and-logical-operators.md

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+#  round/floor a f32 using logical operations and integer arithmetical operations in Rust 
+
+Yith this function you can able to truncate a float f32 using bitwise, logical operations and integer arithmetical operation.  
+The function has not 100% of precisition because ignore most of the bits in the mantissa, but it's often to round small numbers.
+
+```Rust
+fn round(mut f: f32) -> i32 {
+    let sign = f < 0.0;
+    if sign {
+        f = f * -1.0;
+    }
+    
+    let digits = f.to_bits();
+
+    let mut exponent = (digits as i32 >> 23) & (!(1 << 8));
+    let mantissa = (digits - (digits >> 23 << 23)) >> 16 | 1 << 7;
+    
+    exponent -= 127;
+
+    if exponent < 0 {
+        return 0;
+    }
+    let exponent: u32 = 1 << exponent as u32;
+
+    let mut result: i32 = (exponent * mantissa) as i32 / 128;
+    if sign {
+       result *= -1;
+    }
+    result
+}
+
+fn main() {
+    println!("{}", round(15.125));
+    println!("{}", round(14.345));
+    println!("{}", round(-1.555));
+    println!("{}", round(-9.001));
+    println!("{}", round(-999.001));
+    println!("{}", round(-0.5));
+}
+```