NPY_BOOL

The enumeration value for the boolean type, stored as one byte. It may only be set to the values 0 and 1.

NPY_BYTE

NPY_INT8

The enumeration value for an 8-bit/1-byte signed integer.

NPY_SHORT

NPY_INT16

The enumeration value for a 16-bit/2-byte signed integer.

NPY_INT

NPY_INT32

The enumeration value for a 32-bit/4-byte signed integer.

NPY_LONG

Equivalent to either NPY_INT or NPY_LONGLONG, depending on the platform.

NPY_LONGLONG

NPY_INT64

The enumeration value for a 64-bit/8-byte signed integer.

NPY_UBYTE

NPY_UINT8

The enumeration value for an 8-bit/1-byte unsigned integer.

NPY_USHORT

NPY_UINT16

The enumeration value for a 16-bit/2-byte unsigned integer.

NPY_UINT

NPY_UINT32

The enumeration value for a 32-bit/4-byte unsigned integer.

NPY_ULONG

Equivalent to either NPY_UINT or NPY_ULONGLONG, depending on the platform.

NPY_ULONGLONG

NPY_UINT64

The enumeration value for a 64-bit/8-byte unsigned integer.

NPY_HALF

NPY_FLOAT16

The enumeration value for a 16-bit/2-byte IEEE 754-2008 compatible floating point type.

NPY_FLOAT

NPY_FLOAT32

The enumeration value for a 32-bit/4-byte IEEE 754 compatible floating point type.

NPY_DOUBLE

NPY_FLOAT64

The enumeration value for a 64-bit/8-byte IEEE 754 compatible floating point type.

NPY_LONGDOUBLE

The enumeration value for a platform-specific floating point type which is at least as large as NPY_DOUBLE, but larger on many platforms.

NPY_CFLOAT

NPY_COMPLEX64

The enumeration value for a 64-bit/8-byte complex type made up of two NPY_FLOAT values.

NPY_CDOUBLE

NPY_COMPLEX128

The enumeration value for a 128-bit/16-byte complex type made up of two NPY_DOUBLE values.

NPY_CLONGDOUBLE

The enumeration value for a platform-specific complex floating point type which is made up of two NPY_LONGDOUBLE values.

NPY_DATETIME

The enumeration value for a data type which holds dates or datetimes with a precision based on selectable date or time units.

NPY_TIMEDELTA

The enumeration value for a data type which holds lengths of times in integers of selectable date or time units.

NPY_STRING

The enumeration value for ASCII strings of a selectable size. The strings have a fixed maximum size within a given array.

NPY_UNICODE

The enumeration value for UCS4 strings of a selectable size. The strings have a fixed maximum size within a given array.

NPY_OBJECT

The enumeration value for references to arbitrary Python objects.

NPY_VOID

Primarily used to hold struct dtypes, but can contain arbitrary binary data.

Some useful aliases of the above types are

NPY_INTP

The enumeration value for a signed integer type which is the same size as a (void *) pointer. This is the type used by all arrays of indices.

NPY_UINTP

The enumeration value for an unsigned integer type which is the same size as a (void *) pointer.

NPY_MASK

The enumeration value of the type used for masks, such as with the NPY_ITER_ARRAYMASK iterator flag. This is equivalent to NPY_UINT8.

NPY_DEFAULT_TYPE

The default type to use when no dtype is explicitly specified, for example when calling np.zero(shape). This is equivalent to NPY_DOUBLE.

Other useful related constants are

NPY_NTYPES

The total number of built-in NumPy types. The enumeration covers the range from 0 to NPY_NTYPES-1.

NPY_NOTYPE

A signal value guaranteed not to be a valid type enumeration number.

NPY_USERDEF

The start of type numbers used for Custom Data types.

The various character codes indicating certain types are also part of an enumerated list. References to type characters (should they be needed at all) should always use these enumerations. The form of them is NPY_{NAME}LTR where {NAME} can be

BOOL, BYTE, UBYTE, SHORT, USHORT, INT, UINT, LONG, ULONG, LONGLONG, ULONGLONG, HALF, FLOAT, DOUBLE, LONGDOUBLE, CFLOAT, CDOUBLE, CLONGDOUBLE, DATETIME, TIMEDELTA, OBJECT, STRING, VOID

INTP, UINTP

GENBOOL, SIGNED, UNSIGNED, FLOATING, COMPLEX