Function _call

numexpr3/ne3compiler.py:1272–1337

AST function factory for a callable, for one to three arguments. One-function arguments are typical, they may take many forms such as cast operations (:code:`float32(x)`) or transcendentals (:code:`sin(x)`) for example. Two-function arguments are rarer, an example being :

(self: NumExpr, node: ast.AST)

    return outputRegister
           
def _call(self: NumExpr, node: ast.AST) -> NumReg:
    '''
    AST function factory for a callable, for one to three arguments.
    
    One-function arguments are typical, they may take many forms such as cast
    operations (:code:`float32(x)`) or transcendentals (:code:`sin(x)`) for 
    example.

    Two-function arguments are rarer, an example being :code:`atan2(x, y)`. 
    NE3 supports a number of two-function arguments found in :code:`scipy.misc`.

    The only supported three-function argument is :code:`where(test, a, b)`

    ast.Call fields are: (in Python >= 3.4)
    :code:`('func', 'args', 'keywords', 'starargs', 'kwargs')`

    Only `args` is examined.
    '''
    # info( '$ast.Call: %s'%node.func.id )

    argRegisters = [_ASTAssembler[type(arg)](self, arg) for arg in node.args]
    
    if len(argRegisters) == 1:
        argReg0 = argRegisters[0]
        # _cast1: We may have to do a cast here, for example 'cos(<int>A)'
        opSig = (node.func.id, self.lib, argReg0.dchar)

        argReg0, opSig = self._func_cast(argReg0, opSig)
        opCode, self.assignDChar = OPTABLE[opSig]
        outputRegister = self._transmit1(argReg0)

        self._codeStream.write(b''.join((opCode, outputRegister.token, 
                            argReg0.token, _NULL_REG, _NULL_REG)))
        
    elif len(argRegisters) == 2:
        argRegisters = self._cast2(*argRegisters)
        argReg0, argReg1 = argRegisters
        opCode, self.assignDChar = OPTABLE[(node.func.id, self.lib,
                            argReg0.dchar, argReg1.dchar)]
        outputRegister = self._transmit2(argReg0, argReg1)
                
        self._codeStream.write( b''.join((opCode, outputRegister.token, 
                            argReg0.token, argReg1.token, _NULL_REG)))
        
    elif len(argRegisters) == 3: 
        # The where() ternary operator function is currently the _only_
        # 3 argument function
        argReg0, argReg1, argReg2 = argRegisters
        argReg1, argReg2 = self._cast2(argReg1, argReg2)

        opCode, self.assignDChar = OPTABLE[ (node.func.id, self.lib,
                            argReg0.dchar, argReg1.dchar, argReg2.dchar)]
        # Because we know the first register is the bool, it's the least useful temporary to re-use
        # as it almost certainly must be promoted.
        outputRegister = self._transmit3(argReg1, argReg2, argReg0)
                
        self._codeStream.write( b''.join((opCode, outputRegister.token, 
                            argReg0.token, argReg1.token, argReg2.token)))