probminhash 0.1.12

Minhash algorithms for weighted Jaccard index
Documentation 
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//!
//! a Trait for object needing to provide an id in the form of a \[u8\] slice to be fed in Sha hash functions with  
//!
//! The purpose is to get a hash as perfect as possible so the slice returned must identify
//! the object uniquely

/// return a Vec\<u8\> identifying the object.  
/// For example a usize could return to_le_bytes, a 2-uple v = (usize, usize) could return
/// the concatenation of slices obtained for v.0 and v.1.
/// A String can use get_sig from trait Sig.  
/// The purpose of this is to get a u8 slice that can be fed into Sha update methods and so in probminhash3sha
pub trait Sig {
    /// returns the object signature
    fn get_sig(&self) -> Vec<u8>;
}

impl Sig for u8 {
    fn get_sig(&self) -> Vec<u8> {
        vec![*self]
    }
} // end of impl Sig for u8

impl Sig for u16 {
    fn get_sig(&self) -> Vec<u8> {
        Vec::from(self.to_ne_bytes())
    }
} // end of impl Sig for u16

impl Sig for u32 {
    fn get_sig(&self) -> Vec<u8> {
        Vec::from(self.to_ne_bytes())
    }
} // end of impl Sig for u32

impl Sig for u64 {
    fn get_sig(&self) -> Vec<u8> {
        Vec::from(self.to_ne_bytes())
    }
} // end of impl Sig for u32

impl Sig for i16 {
    fn get_sig(&self) -> Vec<u8> {
        Vec::from(self.to_ne_bytes())
    }
} // end of impl Sig for i16

impl Sig for i32 {
    fn get_sig(&self) -> Vec<u8> {
        Vec::from(self.to_ne_bytes())
    }
} // end of impl Sig for i32

impl Sig for Vec<u8> {
    fn get_sig(&self) -> Vec<u8> {
        self.clone()
    }
} // end of impl Sig for <Vec<u8>>

impl Sig for Vec<u16> {
    fn get_sig(&self) -> Vec<u8> {
        let mut c = self.clone();
        let ptr = c.as_mut_ptr();
        let new_len = c.len() * std::mem::size_of::<u16>();
        unsafe { Vec::<u8>::from_raw_parts(ptr as *mut u8, new_len, new_len) }
    }
} // end of impl Sig for <Vec<u16>>

impl Sig for Vec<u32> {
    fn get_sig(&self) -> Vec<u8> {
        let mut c = self.clone();
        let ptr = c.as_mut_ptr();
        let new_len = c.len() * std::mem::size_of::<u32>();
        unsafe { Vec::<u8>::from_raw_parts(ptr as *mut u8, new_len, new_len) }
    }
} // end of impl Sig for <Vec<u32>>

impl Sig for String {
    fn get_sig(&self) -> Vec<u8> {
        let s: &[u8] = self.as_ref();
        s.to_vec()
    }
}