A verifiable quantum advantage towards real world applications: Quantum Echoes 
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      cirq.has_kraus
  
      
    
  
  
  
  
  
    
  
  
    
    
Returns whether the value has a Kraus representation.
cirq.has_kraus(
    val: Any, *, allow_decompose: bool = True
) -> bool
Used in the notebooks
| Args | 
|---|
| val | The value to check. | 
| allow_decompose | Used by internal methods to stop redundant
decompositions from being performed (e.g. there's no need to
decompose an object to check if it is unitary as part of determining
if the object is a quantum channel, when the quantum channel check
will already be doing a more general decomposition check). Defaults
to True. When False, the decomposition strategy for determining
the result is skipped. | 
| Returns | 
|---|
| If valhas a_has_kraus_method and its result is not
NotImplemented, that result is returned. Otherwise, ifvalhas a_has_mixture_method and its result is not NotImplemented, that
result is returned. Otherwise ifvalhas a_has_unitary_method
and its results is not NotImplemented, that result is returned.
Otherwise, if the value has a kraus method return if that
has a non-default value. Returns False if none of these functions
exists. | 
  
  
 
  
    
    
      
    
    
  
       
    
    
  
  
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  Last updated 2025-08-14 UTC.
  
  
  
    
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