loadNpz

Syntax

loadNpz(fileName)

Arguments

filename is a STRING indicating the path of npz file.

Details

Read an npz binary file from Python NumPy and convert it into DolphinDB objects. NaN in npz file is converted into NULL in DolphinDB.

Conversion Table for Python np.array and DolphinDB Objects:

NumPy array	DolphinDB Objects
one-dimensional	vector
two-dimensional	matrix
three-dimensional	tuple (where each element represents a matrix

Data types supported for conversion are: BOOL, CHAR, SHORT, INT, LONG, FLOAT, DOUBLE and STRING (only one-dimensional array is supported).

First Release

1.30.16/2.00.4

Examples

Save npz file in Python:

import numpy as np
a = np.array([[[97, 98]]], dtype=np.int8)
a1 = np.array(['133', '211', '3dds', 'ddd4', 'e5', 'w6'])
b1 = np.array([[0.7, 0.8, 9.2], [0, np.nan, np.nan], [1.5, 2.8, 0.2]])
c1 = np.array([[[0.2, 3.3], [1.9, 4.3]], [[5, 6], [1, 2]]])
np.savez('my_path/array_save.npz', char=a, a1=a1, b1=b1, c1=c1)

Load npz file in DolphinDB:

$ path="my_path/array_save.npz"
$ loadNpz(path)
a1->[133,211,3dds,ddd4,e5,w6]
char->(#0  #1
'a' 'b'
)
c1->(#0  #1
0.2 3.3
1.9 4.3
,#0 #1
5  6
1  2
)
b1->
#0  #1  #2
0.7 0.8 9.2
0
1.5 2.8 0.2

Related Function: loadNpy