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Troubleshooting

License issues

The following section outlines practical information useful when dealing with getting access to and managing licenses for PyKX.

Accessing a license valid for PyKX

A number of trial and enterprise type licenses exist for q/kdb+. Not all licenses for q/kdb+ however are valid for PyKX. In particular users require access to a license which contains the feature flags pykx and embedq which provide access to the PyKX functionality. The following locations can be used for the retrieval of evaluation/personal licenses

  • For non-commercial personal users you can access a 12 month kdb+ license with PyKX enabled here.
  • For commercial evaluation you can download a 30 day PyKX license here.

For non-personal or non-commercial usage please contact sales@kx.com.

Once you have access to your license you can install the license following the walkthrough provided here or through installation using the function kx.license.install as follows

>>> import pykx as kx
>>> kx.license.install('/path/to/downloaded/kc.lic')

Initialization failing with a 'embedq' error

Failure to initialize PyKX while raising an error embedq indicates that the license you are attempting to use for PyKX in licensed modality does not have the sufficient feature flags necessary to run PyKX. To access a license which does allow for running PyKX in this modality please following the instructions here to get a new license with appropriate feature flags.

Initialization failing with a 'kc.lic' error

If after initially completing the installation guide for PyKX here you receive the following error:

pykx.exceptions.PyKXException: Failed to initialize embedded q. Captured output from initialization attempt:
    '2023.09.02T21:28:45.699 licence error: kc.lic

It usually indicates that your license was not correctly written to disk or a license could not be found, to check that the installed license matches the license you expect.

The following shows a successful check being completed:

>>> import pykx as kx
>>> kx.license.check('/path/to/downloaded/kc.lic')
    True

The following shows an example of a failed check:

>>> import pykx as kx
>>> kx.license.check('/path/to/incorrect/license.txt')
Supplied license information does not match.
Please consider reinstalling your license using pykx.util.install_license

On disk license:
b'Atc/wy/gMjZgIdn1KlT3JVWfVmPk55dtb0YJVes5V4ed9Zxt9UVr8G/A1Q3aWiQEkfjGbwvlJU3GXpUergObvzxGN1iyYG\nZasG5s8vevfAI2ttndt//Y2th\nrryoQRm9Dy+DIIcmSufwomL+\nPMJkZacYc9DM6ipnQsL0KvLwLXLrQC1fBLV2pZHCdYC/nX/KM6uslgip4EoTxZTcx1pQPyTx56QKD4K4JBNimO929w/0+v4Hy2x+DIS3n89vpGmtVvjjFRQtsF6Sjnd+6RnFGk13hRL/DlqHTv2XbZgVv++YOCIc7G55KL6PVJY\npB\n66lq9OiZCEdq2GFJLCn2T\nNWGJPT2s1YDAKsAPI5W3PqJkC2UeV17gPG4gxlCSHr0kfacINbEJ0kSTm/UsuEBZ5B/jvR/jU7rFErcd9PECeQA1kXB19fa4hgvbd+SxWTPxMUKbiHThHk6X0Bi3T7WAQ+sZWsEWwkMncd+mOGS\n3D+bRav2nfOpKckj8rCdvYum3U8PDv6IHP=S+\nLaCnJM0yqNjW9xGyog5ml\nbX2k3mBRyBjbJH/1OWTcIg7uDYxxoMtDOCJjeBdSqI=aK+5FVTVarfowvudv7QsMGeohGaJMyczNWVPPjsbyvsxbAwdXvJUuP0jcFCFVeF\n'

Supplied string content:
b'8n\nD+HkcJ93xW4oOEtH\nIZxeWkA1glv5wJ5wE2Fsmbc4lg2ntT9JpsclE1hFeG/Ox/jM4=6GjXD2VNpiCAJ80DNVcXuDB+IPEnP22DMGvBIolJt2pdy9kooGZNQpr6svIkRWX/0m/SbydbQOQUVvfNTxsDjZvvsCiGkdQtygs3sDEJbxsT+KfjqJ7Sd6RQ/47HJHG4JyIWdhmvEBVGSLBa5mdAaCLWdCrga3hHZbW3F4e/l3K4nOQvU91WEiMd6PT061r66AOYmjGACCXqmQ9kSsJfMTXPRi9M2i93Oyv895kFVKdZCLCdKdaow790RcjwnKjFFOERGcge=lZdRtp2BL\nA+JbixvTIKTObmfqr7uPYsGQLfXSFnQCq7jbt3yxv1ZPjvjYLPTx7YKIvgo+ITG6vyY\ne+cfwaW1g0tlvFTcVSVb/sxUvvLCLiWMdxGjt5JUxV3GaSm9ysHVk5MrTDpp/5qqXes1\n/BOXsD\n2DmS/QSZr/Mt+Vc2baKuxPw1w5YnGVuY6vHxHffABzkn+WPcguabr86JcmIAcC0zc2TLkbufBPJewYka9PIt1Ng2\n83NKe13huPU\nohnryYVIMPyjrTWpDid+yC5kSGVeP0/5+r\nJvLmFZUB/n0RUjgMZU5V++GPU1QnCBa+\n"
False
The following shows a successful check being completed:

```python
>>> import pykx as kx
>>> license_string = 'Atc/wy/gMjZgIdn1KlT3JVWfVmPk55dtb0YJVes5V4ed9Zxt9UVr8G/A1Q3aWiQEkfjGbwvlJU3GXpUergObvzxGN1iyYG\nZasG5s8vevfAI2ttndt//Y2th\nrryoQRm9Dy+DIIcmSufwomL+\nPMJkZacYc9DM6ipnQsL0KvLwLXLrQC1fBLV2pZHCdYC/nX/KM6uslgip4EoTxZTcx1pQPyTx56QKD4K4JBNimO929w/0+v4Hy2x+DIS3n89vpGmtVvjjFRQtsF6Sjnd+6RnFGk13hRL/DlqHTv2XbZgVv++YOCIc7G55KL6PVJY\npB\n66lq9OiZCEdq2GFJLCn2T\nNWGJPT2s1YDAKsAPI5W3PqJkC2UeV17gPG4gxlCSHr0kfacINbEJ0kSTm/UsuEBZ5B/jvR/jU7rFErcd9PECeQA1kXB19fa4hgvbd+SxWTPxMUKbiHThHk6X0Bi3T7WAQ+sZWsEWwkMncd+mOGS\n3D+bRav2nfOpKckj8rCdvYum3U8PDv6IHP=S+\nLaCnJM0yqNjW9xGyog5ml\nbX2k3mBRyBjbJH/1OWTcIg7uDYxxoMtDOCJjeBdSqI=aK+5FVTVarfowvudv7QsMGeohGaJMyczNWVPPjsbyvsxbAwdXvJUuP0jcFCFVeF\n'
>>> kx.license.check(license_string, format = 'STRING')
True
```

The following shows an example of a failed check:

```python
>>> import pykx as kx

license_string = '8n\nD+HkcJ93xW4oOEtH\nIZxeWkA1glv5wJ5wE2Fsmbc4lg2ntT9JpsclE1hFeG/Ox/jM4=6GjXD2VNpiCAJ80DNVcXuDB+IPEnP22DMGvBIolJt2pdy9kooGZNQpr6svIkRWX/0m/SbydbQOQUVvfNTxsDjZvvsCiGkdQtygs3sDEJbxsT+KfjqJ7Sd6RQ/47HJHG4JyIWdhmvEBVGSLBa5mdAaCLWdCrga3hHZbW3F4e/l3K4nOQvU91WEiMd6PT061r66AOYmjGACCXqmQ9kSsJfMTXPRi9M2i93Oyv895kFVKdZCLCdKdaow790RcjwnKjFFOERGcge=lZdRtp2BL\nA+JbixvTIKTObmfqr7uPYsGQLfXSFnQCq7jbt3yxv1ZPjvjYLPTx7YKIvgo+ITG6vyY\ne+cfwaW1g0tlvFTcVSVb/sxUvvLCLiWMdxGjt5JUxV3GaSm9ysHVk5MrTDpp/5qqXes1\n/BOXsD\n2DmS/QSZr/Mt+Vc2baKuxPw1w5YnGVuY6vHxHffABzkn+WPcguabr86JcmIAcC0zc2TLkbufBPJewYka9PIt1Ng2\n83NKe13huPU\nohnryYVIMPyjrTWpDid+yC5kSGVeP0/5+r\nJvLmFZUB/n0RUjgMZU5V++GPU1QnCBa+\n' >>> kx.license.check(license_string, format = 'STRING') Supplied license information does not match. Please consider reinstalling your license using pykx.util.install_license

On disk license:
b'Atc/wy/gMjZgIdn1KlT3JVWfVmPk55dtb0YJVes5V4ed9Zxt9UVr8G/A1Q3aWiQEkfjGbwvlJU3GXpUergObvzxGN1iyYG\nZasG5s8vevfAI2ttndt//Y2th\nrryoQRm9Dy+DIIcmSufwomL+\nPMJkZacYc9DM6ipnQsL0KvLwLXLrQC1fBLV2pZHCdYC/nX/KM6uslgip4EoTxZTcx1pQPyTx56QKD4K4JBNimO929w/0+v4Hy2x+DIS3n89vpGmtVvjjFRQtsF6Sjnd+6RnFGk13hRL/DlqHTv2XbZgVv++YOCIc7G55KL6PVJY\npB\n66lq9OiZCEdq2GFJLCn2T\nNWGJPT2s1YDAKsAPI5W3PqJkC2UeV17gPG4gxlCSHr0kfacINbEJ0kSTm/UsuEBZ5B/jvR/jU7rFErcd9PECeQA1kXB19fa4hgvbd+SxWTPxMUKbiHThHk6X0Bi3T7WAQ+sZWsEWwkMncd+mOGS\n3D+bRav2nfOpKckj8rCdvYum3U8PDv6IHP=S+\nLaCnJM0yqNjW9xGyog5ml\nbX2k3mBRyBjbJH/1OWTcIg7uDYxxoMtDOCJjeBdSqI=aK+5FVTVarfowvudv7QsMGeohGaJMyczNWVPPjsbyvsxbAwdXvJUuP0jcFCFVeF\n'

Supplied string content:
b'8n\nD+HkcJ93xW4oOEtH\nIZxeWkA1glv5wJ5wE2Fsmbc4lg2ntT9JpsclE1hFeG/Ox/jM4=6GjXD2VNpiCAJ80DNVcXuDB+IPEnP22DMGvBIolJt2pdy9kooGZNQpr6svIkRWX/0m/SbydbQOQUVvfNTxsDjZvvsCiGkdQtygs3sDEJbxsT+KfjqJ7Sd6RQ/47HJHG4JyIWdhmvEBVGSLBa5mdAaCLWdCrga3hHZbW3F4e/l3K4nOQvU91WEiMd6PT061r66AOYmjGACCXqmQ9kSsJfMTXPRi9M2i93Oyv895kFVKdZCLCdKdaow790RcjwnKjFFOERGcge=lZdRtp2BL\nA+JbixvTIKTObmfqr7uPYsGQLfXSFnQCq7jbt3yxv1ZPjvjYLPTx7YKIvgo+ITG6vyY\ne+cfwaW1g0tlvFTcVSVb/sxUvvLCLiWMdxGjt5JUxV3GaSm9ysHVk5MrTDpp/5qqXes1\n/BOXsD\n2DmS/QSZr/Mt+Vc2baKuxPw1w5YnGVuY6vHxHffABzkn+WPcguabr86JcmIAcC0zc2TLkbufBPJewYka9PIt1Ng2\n83NKe13huPU\nohnryYVIMPyjrTWpDid+yC5kSGVeP0/5+r\nJvLmFZUB/n0RUjgMZU5V++GPU1QnCBa+\n'
False
```

Environment issues

The following section outlines how a user can get access to a verbose set of environment configuration associated with PyKX. This information is helpful when debugging your environment and should be provided if possible with support requests.

>>> import pykx as kx
>>> kx.util.debug_environment()  # see below for output
Output 
>>> kx.util.debug_environment()
missing q binary at '/usr/local/anaconda3/lib/python3.8/site-packages/pykx/lib/m64/q'
**** PyKX information ****
pykx.args: ()
pykx.qhome: /usr/local/anaconda3/lib/python3.8/site-packages/pykx/lib
pykx.qlic: /usr/local/anaconda3/lib/python3.8/site-packages/pykx/lib
pykx.licensed: True
pykx.__version__: 1.5.3rc2.dev525+g41f008ad
pykx.file: /usr/local/anaconda3/lib/python3.8/site-packages/pykx/util.py

**** Python information ****
sys.version: 3.8.3 (default, Jul  2 2020, 11:26:31) 
[Clang 10.0.0 ]
pandas: 1.5.3
numpy: 1.24.4
pytz: 2022.7.1
which python: /usr/local/anaconda3/bin/python
which python3: /usr/local/anaconda3/bin/python3

**** Platform information ****
platform.platform: macOS-10.16-x86_64-i386-64bit

**** Environment Variables ****
IGNORE_QHOME: 
PYKX_IGNORE_QHOME: 
PYKX_KEEP_LOCAL_TIMES: 
PYKX_ALLOCATOR: 
PYKX_GC: 
PYKX_LOAD_PYARROW_UNSAFE: 
PYKX_MAX_ERROR_LENGTH: 
PYKX_NOQCE: 
PYKX_Q_LIB_LOCATION: 
PYKX_RELEASE_GIL: 
PYKX_Q_LOCK: 
PYKX_ENABLE_PANDAS_API: 
QARGS: 
QHOME: /usr/local/anaconda3/lib/python3.8/site-packages/pykx/lib
QLIC: 
PYKX_DEFAULT_CONVERSION: 
PYKX_SKIP_UNDERQ: 
PYKX_UNSET_GLOBALS: 
SKIP_UNDERQ: 
UNSET_PYKX_GLOBALS: 

**** License information ****
pykx.qlic directory: True
pykx.lic writable: True
pykx.qhome lics: ['kc.lic']
pykx.qlic lics: ['kc.lic']

**** q information ****
which q: /usr/local/anaconda3/bin/q
q info:

Issues running PyKX in a subprocess?

Internally PyKX makes use of a number of variables/environment variables which are persisted within the Python/q process within imports PyKX. Due to how Python subprocesses work with respect to inheriting environment variables users who attempt to spawn a subprocess dependent on PyKX will run into a Segmentation Fault.

To avoid this subprocesses should be spawned while making use of the kx.PyKXReimport functionality as follows:

import pykx as kx
import subprocess
with kx.PyKXReimport():
    subprocess.Popen(['python', 'file.py']) # Run Python with a file that imports PyKX

For more information on the PyKXReimport functionality see its API documentation here.