2.1.6. HDF5 in Python with NAPI

A single code example is provided in this section that writes 3-D data to a NeXus HDF5 file in the Python language using the NAPI: NeXus Application Programmer Interface (frozen).

The data to be written to the file is a simple three-dimensional array (2 x 3 x 4) of integers. The single dataset is intended to demonstrate the order in which each value of the array is stored in a NeXus HDF5 data file.

2.1.6.1. NAPI Python Example: write simple NeXus file

#!/usr/bin/python

import sys
import nxs
import numpy

a = numpy.zeros((2,3,4),dtype=numpy.int)
val = 0
for i in range(2):
    for j in range(3):
        for k in range(4):
            a[i,j,k] = val
            val = val + 1

nf = nxs.open("simple3D.h5", "w5")

nf.makegroup("entry","NXentry")
nf.opengroup("entry","NXentry")

nf.makegroup("data","NXdata")
nf.opengroup("data","NXdata")
nf.putattr("signal","test")

nf.makedata("test",'int32',[2,3,4])
nf.opendata("test")
nf.putdata(a)
nf.closedata()

nf.closegroup() # NXdata
nf.closegroup() # NXentry

nf.close()

exit