Numpy Scalars(标量)

在Python中只有一个整型和和一个浮点型的数据类型,而在NumPy中则由24种不同的数据类型.

Booleans(布尔型)

Type	Remarks	Character code
bool_	compatible: Python bool	?’
bool8	8 bits

Integers(整型)

类型	注释	字符串码
byte	compatible: C char	b’
short	compatible: C short	h’
intc	compatible: C int	i’
int_	compatible: Python int	l’
longlong	compatible: C long long	q’
intp	large enough to fit a pointer	p’
int8	8 bits
int16	16 bits
int32	32 bits
int64	64 bits

Unsigned integers(无符号整型)

类型	标注	字符串码
ubyte	compatible: C unsigned char	B’
ushort	compatible: C unsigned short	H’
uintc	compatible: C unsigned int	I’
uint	compatible: Python int	L’
ulonglong	compatible: C long long	Q’
uintp	large enough to fit a pointer	P’
uint8	8 bits
uint16	16 bits
uint32	32 bits
uint64	64 bits

Floating-point numbers(浮点型)

类型	标注	字符串码
half		e’
single	compatible: C float	f’
double	compatible: C double
float_	compatible: Python float	d’
longfloat	compatible: C long float	g’
float16	16 bits
float32	32 bits
float64	64 bits
float96	96 bits, platform?
float128	128 bits, platform?

Complex floating-point numbers(复杂浮点型)

类型	标注	字符码
csingle		F’
complex_	compatible: Python complex	D’
clongfloat		G’
complex64	two 32-bit floats
complex128	two 64-bit floats
complex192	two 96-bit floats, platform?
complex256	two 128-bit floats, platform?

常用数据类型

类型	字符码
boolean	b’
(signed) integer	i’
unsigned integer	u’
floating-point	f
complex-floating point	c
timedelta	m
datetime	M
(Python) objects	O
(byte-)string	S, a
Unicode	U
raw data (void)	V’

例子:

>>> dt = np.dtype('i4')   # 32-bit signed integer
>>> dt = np.dtype('f8')   # 64-bit floating-point number
>>> dt = np.dtype('c16')  # 128-bit complex floating-point number
>>> dt = np.dtype('a25')  # 25-character string

参考文献:
https://docs.scipy.org/doc/numpy/reference/arrays.scalars.html#arrays-scalars-built-in