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# complex
# 目录
* [相关位置文件](#相关位置文件)
* [内存构造](#内存构造)
* [示例](#示例)
# 相关位置文件
* cpython/Objects/complexobject.c
* cpython/Include/complexobject.h
* cpython/clinic/complexobject.c.h
# 内存构造
**PyComplexObject** 内部存储了两个双精度浮点数, 处理过程和表示方法都和 [float](https://github.com/zpoint/CPython-Internals/blob/master/BasicObject/float/float_cn.md) 对象很类似
# 示例
```python3
c = complex(0, 1)
```
```python3
d = complex(0.1, -0.2)
```
我们来读下加法部分的代码
```c
Py_complex
_Py_c_sum(Py_complex a, Py_complex b)
{
Py_complex r;
r.real = a.real + b.real;
r.imag = a.imag + b.imag;
return r;
}
static PyObject *
complex_add(PyObject *v, PyObject *w)
{
Py_complex result;
Py_complex a, b;
TO_COMPLEX(v, a); // 检查下类型, 如果不为 PyComplexObject 需要先转换为 PyComplexObject
TO_COMPLEX(w, b);
PyFPE_START_PROTECT("complex_add", return 0) // 在 3.7 版本之后就没用了
result = _Py_c_sum(a, b); // sum the complex
PyFPE_END_PROTECT(result) // 在 3.7 版本之后就没用了
return PyComplex_FromCComplex(result);
}
```
加法看起来比较简单, 把实数 **real** 部分相加, 把虚数 **imag** 部分相加, 并返回相加后的整个结构
加减乘数, 负号, 平方等操作都很类似
```python3
>>> e = c + d
>>> repr(e)
'(0.1+0.8j)'
```
