从Paraview 4.2中提取Python脚本中的数据

我试图使用Paraview 4.2从Python脚本中的一个片段中提取数据。我有这样的想法：

from paraview.numpy_support import vtk_to_numpy
from paraview.simple import *
import os

os.environ["DISPLAY"] = ":0"
paraview.simple._DisableFirstRenderCameraReset()

# create a new 'XDMF Reader'
xDMFtemporalFieldsxmf = XDMFReader(FileNames=['<pathtodata>/XDMF.temporalFields.xmf'])

# Properties modified on xDMFtemporalFieldsxmf
xDMFtemporalFieldsxmf.PointArrayStatus = ['DensityProperty-mesh', 'VelocityField']
xDMFtemporalFieldsxmf.CellArrayStatus = []

# create a new 'Slice'
slice1 = Slice(Input=xDMFtemporalFieldsxmf)

# create a new 'Clip'
clip1 = Clip(Input=slice1)
clip1.ClipType = 'Scalar'
clip1.Value = 1200.0

编辑-此操作的输出为：

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-11-e34f36729df1> in <module>()
      1 data = servermanager.Fetch(clip1)
      2 d2 = data.GetPoints()
----> 3 xyz = zeros((d2.GetNumberOfPoints(), 3))
      4 for i in range(d2.GetNumberOfPoints()):
      5     xyz[i,:] = data.GetPoint(i)

AttributeError: 'NoneType' object has no attribute 'GetNumberOfPoints'

给出：

None
<vtk.numpy_interface.dataset_adapter.VTKNoneArray object at 0x7f57c4a75390>

无

使用前面的方法会出现什么错误。它应该会起作用。更好的方法如下：

# ensure that the clip1 filter is updated.
clip1.UpdatePipeline()

rawData = servermanager.Fetch(clip1)

import vtk.numpy_interface.dataset_adapter as dsa

# Wrap the raw data object to access NumPy friendly API
data = dsa.WrapDataObject(data)

print data.Points
VTKArray([[ -5.        ,  -5.        ,  -9.15493107],
   [ -3.        ,  -5.        ,  -9.75046444],
   [ -2.        ,  -5.        ,  -9.50859547],
   ..., 
   [  3.04815888,   3.        ,  10.        ],
   [  4.24629259,   3.        ,  10.        ],
   [  4.        ,   3.25505328,  10.        ]], dtype=float32)


# To access the point data array named VelocityField
print data.PointData["VelocityField"]

---

这是正确的——我认为这是一种更好的访问数据的方法。我遇到了问题，因为我的初始代码不够明确。它是通过确保所有剪辑和切片都有足够的信息正确处理而修复的。仅供参考，VTKNoneArray返回时，数据集中不存在具有该名称的数组。

>> clip1.UpdatePipeline()
>> rawData = servermanager.Fetch(clip1)
>> import vtk.numpy_interface.dataset_adapter as dsa
>> # Wrap the raw data object to access NumPy friendly API
>> data = dsa.WrapDataObject(rawData) # Note I changed this from Utkarsh's "data" to "rawData"
>> print data.Points
>> print data.PointData["VelocityField"]

None
<vtk.numpy_interface.dataset_adapter.VTKNoneArray object at 0x7f57c4a75390>

# ensure that the clip1 filter is updated.
clip1.UpdatePipeline()

rawData = servermanager.Fetch(clip1)

import vtk.numpy_interface.dataset_adapter as dsa

# Wrap the raw data object to access NumPy friendly API
data = dsa.WrapDataObject(data)

print data.Points
VTKArray([[ -5.        ,  -5.        ,  -9.15493107],
   [ -3.        ,  -5.        ,  -9.75046444],
   [ -2.        ,  -5.        ,  -9.50859547],
   ..., 
   [  3.04815888,   3.        ,  10.        ],
   [  4.24629259,   3.        ,  10.        ],
   [  4.        ,   3.25505328,  10.        ]], dtype=float32)


# To access the point data array named VelocityField
print data.PointData["VelocityField"]