无法在nopython上下文中强制进出对象：python之后出错

Question

从here跟进，Numba在我的机器上终于工作（几周后），没有任何奇怪的缩进错误。

我已经在链接问题的解决方案中实现了它。

但是，我现在从Numba那里得到这一系列错误，最后一行是它不能coerce to or from object in nopython context：

Traceback (most recent call last):
  File "C:\Users\app\Documents\Python Scripts\gbc_classifier_train.py", line 19, in <module>
    import gentleboost_c_class_jit_v6_nolimit as gbc
  File "C:\Users\app\Documents\Python Scripts\gentleboost_c_class_jit_v6_nolimit.py", line 26, in <module>
    @jit(void(object_, float_[:,:], int_[:], int_))
  File "C:\Users\app\Anaconda\lib\site-packages\numba\decorators.py", line 224, in _jit_decorator
    nopython=nopython, func_ast=func_ast, **kwargs)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\decorators.py", line 133, in compile_function
    func_env = pipeline.compile2(env, func, restype, argtypes, func_ast=func_ast, **kwds)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 144, in compile2
    post_ast = pipeline(func_ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 191, in __call__
    ast = self.transform(ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 656, in transform
    ast = stage(ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 641, in _stage
    return _check_stage_object(stage_obj)(ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 194, in __call__
    ast = self.transform(ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 474, in transform
    return transformer.visit(ast)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 311, in visit_ControlBlock
    self.visitlist(node.body)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 286, in visitlist
    list[:] = _flatmap(self.visit, list)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 33, in _flatmap
    res = func(elem)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 306, in generic_visit
    new_node = self.visit(old_value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 311, in visit_ControlBlock
    self.visitlist(node.body)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 286, in visitlist
    list[:] = _flatmap(self.visit, list)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 33, in _flatmap
    res = func(elem)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 306, in generic_visit
    new_node = self.visit(old_value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 311, in visit_ControlBlock
    self.visitlist(node.body)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 286, in visitlist
    list[:] = _flatmap(self.visit, list)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\visitors.py", line 33, in _flatmap
    res = func(elem)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 306, in generic_visit
    new_node = self.visit(old_value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 297, in generic_visit
    value = self.visit(value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\array_expressions.py", line 100, in visit_Assign
    node.value = self.visit(node.value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\ast.py", line 306, in generic_visit
    new_node = self.visit(old_value)
  File "C:\Users\app\Anaconda\lib\ast.py", line 241, in visit
    return visitor(node)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\array_expressions.py", line 136, in visit_BinOp
    return self.visit_elementwise(elementwise, node)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\array_expressions.py", line 84, in visit_elementwise
    return self.register_array_expression(node)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\array_expressions.py", line 272, in register_array_expression
    wrap=False, link=False, nopython=True,
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 90, in run_pipeline2
    post_ast = pipeline(func_ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 191, in __call__
    ast = self.transform(ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 656, in transform
    ast = stage(ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 641, in _stage
    return _check_stage_object(stage_obj)(ast, env)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\pipeline.py", line 202, in __call__
    reporting.report(env, exc=e)
  File "C:\Users\app\Anaconda\lib\site-packages\numba\reporting.py", line 181, in report
    raise exc
numba.error.NumbaError: (see below)
--------------------- Numba Encountered Errors or Warnings ---------------------
Error 133:22: Cannot coerce to or from object in nopython context
--------------------------------------------------------------------------------

这是什么意思？我希望这并不意味着我不能使用对象！

修改

我编辑了所有相关代码，以便我不再传递任何对象，现在定义如下：

@jit(float_[:,:,:](float_[:,:], int_[:], int_))
def train_function(X, y, H):

但是我仍然会收到这个错误，除非它现在不是Error:133:22，而是：

Error 176:22: Cannot coerce to or from object in nopython context

Answer 1

我发现某个地方Numba无法直接识别np.dot()，Error: 176:22指向第176行，我在那里使用np.dot()。这是相关的一行：

 dot = 1. + np.dot(X1, g1) - np.dot(X1,gc)

所以我把它们的点产品转换成浮点数，它起作用了：

dot = 1. + float(np.dot(X1, g1)) - float(np.dot(X1,gc))