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Python module Cupy function gives error when using cupy.einsum()

I am dealing with a problem with Cupy. I am currently using Cupy and it works great at a very satisfactory high speed. But I have a problem when I use cupy.einsum() method
I am using the same syntax with Numpy without any error. But when using Cupy it gives me an error. Here is the code section
import numpy as np
A = np.random.randn(2,3,10)
B = np.random.randn(3,4)
C = np.einsum('ijk,jl->ijl',A,B)
This works quite well and I get the result that I want consistently. However, when I write the same code with Cupy
import cupy as cp
A = cp.random.randn(2,3,10)
B = cp.random.randn(3,4)
C = cp.einsum('ijk,jl->ijl',A,B)
When I run this, A and B are calculated. But It gives me an error when calculating C. This is the error:
Traceback (most recent call last):
File "", line 4, in
C = cp.einsum('ijk,jl->ijl',A,B)
File
"C:\Users\Okan\anaconda3\lib\site-packages\cupy\linalg\einsum.py",
line 389, in einsum
result_dtype = cupy.result_type(*operands) if dtype is None else dtype
File "<array_function internals>", line 6, in result_type
TypeError: no implementation found for 'numpy.result_type' on types
that implement array_function: [<class 'cupy.core.core.ndarray'>]
I would be so glad if you have an idea or solution about this issue.
Thank you.

For those who are experiencing the same problem, open a new environment in Conda and install the python version above 3.9. After that, when you install cupy by
conda install cupy
it will directly install the latest version (v.7.8 or higher). The problem was based on the version of the cupy. After upgarding, the problem fixed.

Open3d Python, Type error using TriangleMesh.create_from_point_cloud_alpha_shape()

I am trying to use open3d to create an "alphahull" around a set of 3d points using TriangleMesh. However I get a TypeError.
import open3d as o3d
import numpy as np
xx =np.asarray([[10,21,18], [31,20,25], [36,20,24], [33,19,24], [22,25,13], [25,19,24], [22,26,10],[29,19,24]])
cloud = o3d.geometry.PointCloud()
cloud.points = o3d.utility.Vector3dVector(xx)
mesh = o3d.geometry.TriangleMesh.create_from_point_cloud_alpha_shape(pcd=cloud, alpha=10.0)
output:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: create_from_point_cloud_alpha_shape(): incompatible function arguments. The following argument types are supported:
1. (pcd: open3d.open3d.geometry.PointCloud, alpha: float, tetra_mesh: open3d::geometry::TetraMesh, pt_map: List[int]) -> open3d.open3d.geometry.TriangleMesh
The error says the object I am passing the function is the wrong type. But when I check the type I get this:
>>print(type(cloud))
<class 'open3d.open3d.geometry.PointCloud'>
Please can someone help me with this error?
Note: A comment on this post Python open3D no attribute 'create_coordinate_frame' suggested it might be a problem with the installation and that a solution was to compile the library from source. So I compiled the library from source. After this ran
make install-pip-package. Though I am not sure it completed correctly because I couldn't import open3d in python yet; see output of installation: https://pastebin.com/sS2TZfTL
(I wasn't sure if that command was supposed to complete the installation, or if you were still required to run pip? After I ran python3 -m pip install Open3d I could import the library in python.)

Bug in bindings of current release (v0.9.0):
https://github.com/intel-isl/Open3D/issues/1621
Fix for master:
https://github.com/intel-isl/Open3D/pull/1624
Workaround:
tetra_mesh, pt_map = o3d.geometry.TetraMesh.create_from_point_cloud(pcd)
mesh = o3d.geometry.TriangleMesh.create_from_point_cloud_alpha_shape(pcd, alpha, tetra_mesh, pt_map)

How to use "xphoto_WhiteBalancer.balanceWhite" with Python and OpenCV?

I am looking for a straightforward way of applying automatic white balance to an image.
I found some official documentation about a balanceWhite() method: cv::xphoto::WhiteBalancer Class Reference
However, I have an obscure error when I try to call the function as shown in the example.
image = cv2.xphoto_WhiteBalancer.balanceWhite(image)
Raises:
Traceback (most recent call last):
File "C:\Users\Delgan\main.py", line 80, in load
image = cv2.xphoto_WhiteBalancer.balanceWhite(image)
TypeError: descriptor 'balanceWhite' requires a 'cv2.xphoto_WhiteBalancer' object but received a 'numpy.ndarray'
If then I try to use a cv2.xphoto_WhiteBalancer object as required:
balancer = cv2.xphoto_WhiteBalancer()
cv2.xphoto_WhiteBalancer.balanceWhite(balancer, image)
It raises:
Traceback (most recent call last):
File "C:\Users\Delgan\main.py", line 81, in load
cv2.xphoto_WhiteBalancer.balanceWhite(balancer, image)
TypeError: Incorrect type of self (must be 'xphoto_WhiteBalancer' or its derivative)
Did anyone succeeded to use this feature with Python 3.6 and OpenCV 3.4?
I also tried with derived classes GrayworldWB, LearningBasedWB and SimpleWB but errors are the same.

The answer can be found in the xphoto documentation.
The appropriate methods to create the WB algorithms are createSimpleWB(), createLearningBasedWB() and createGrayworldWB().
Example:
wb = cv2.xphoto.createGrayworldWB()
wb.setSaturationThreshold(0.99)
image = wb.balanceWhite(image)
Here is a sample file in the official OpenCV repository: modules/xphoto/samples/color_balance_benchmark.py

OpenCV Error: Bad argument in ERClassifierNM1

I run opencv 3.2.0, ubuntu 14.04, and latest opencv_contrib.
I run examine:
https://github.com/opencv/opencv_contrib/blob/master/modules/text/samples/textdetection.py
But it have show err:
$ python textdetection.py scenetext_word01.jpg
textdetection.py
A demo script of the Extremal Region Filter algorithm described in:
Neumann L., Matas J.: Real-Time Scene Text Localization and Recognition, CVPR 2012
Extracting Class Specific Extremal Regions from 9 channels ...
(...) this may take a while (...)
OpenCV Error: Bad argument (Default classifier file not found!) in ERClassifierNM1, file /home/vietnam/opencv_and_contri/opencv_contrib/modules/text/src/erfilter.cpp, line 1022
Traceback (most recent call last):
File "textdetection.py", line 38, in <module>
erc1 = cv2.text.loadClassifierNM1(pathname+'/trained_classifierNM1.xml')
cv2.error: /home/vietnam/opencv_and_contri/opencv_contrib/modules/text/src/erfilter.cpp:1022: error: (-5) Default classifier file not found! in function ERClassifierNM1
How to solve this?

Try using relative paths in the parameters for cv2.text.loadClassifierNM1() and cv2.text.loadClassifierNM2()
So now that part of the code looks like this:
erc1 = cv2.text.loadClassifierNM1('./trained_classifierNM1.xml')
er1 = cv2.text.createERFilterNM1(erc1,16,0.00015,0.13,0.2,True,0.1)
erc2 = cv2.text.loadClassifierNM2('./trained_classifierNM2.xml')
er2 = cv2.text.createERFilterNM2(erc2,0.5)
I'm not sure why this works (it did for me), but I tried this after looking at a solution posted for a similar problem in VS2015 here: https://github.com/cesardelgadof/OpenCVBinaries/issues/1
Hope this helps.

Trying with absolute path e.g. "/usr/lib/opencv-3.2.0/opencv_contrib-3.2.0/modules/text/samples/trained_classifierNM1.xml" worked in my case for Ubuntu 16.04, C++

Math domain error in python when using log

Here is what I am writing:
>>> import math
>>> 2/3*math.log(2/3,2)
Here is the error I'm getting:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: math domain error
Can someone please explain what I'm doing wrong?
Thanks.

I'm assuming this is Python 2.7.
In 2.7, 2/3 evaluates to 0 since division floors by default. Therefore you're attempting a log 0, hence the error. Python 3 on the other hand does floating point division by default.
To get the correct behaviour you can either:
from __future__ import division, which gives you Python 3 division behaviour in Python 2.7.
Replace each 2/3 with 2/float(3), or 2/3.0.

The problem is that you are probably using python 2.7. In this version 2/3 gives as result 0 (zero). And log function is not defined for 0. Try this:
2/3.0*math.log(2/3.0,2)
In Python 3.5 this problem does not happen.