### Install SWAT from PyPI

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/install.md

Use this command to install the latest release of the SWAT package from the Python Package Index (PyPI).

```bash
pip install swat
```

--------------------------------

### Install SWAT from GitHub Archive (REST Interface Only)

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/install.md

Install SWAT from a GitHub source code archive, which supports only the CAS REST interface. Replace X.X.X with the desired release version.

```bash
pip install https://github.com/sassoftware/python-swat/archive/vX.X.X.tar.gz
```

--------------------------------

### Install SWAT from GitHub Release (Binary Protocol)

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/install.md

Install a specific release of SWAT from GitHub, suitable for platforms requiring the binary protocol. Replace X.X.X and platform with your specific version and target system.

```bash
pip install https://github.com/sassoftware/python-swat/releases/download/vX.X.X/python-swat-X.X.X-platform.tar.gz
```

--------------------------------

### Example Authinfo Entry

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

An example entry for an authinfo file, specifying the host, port, username, and password for a CAS connection. Ensure file permissions are set to 0600 for security.

```default
host cas.my-company.com port 12354 user user01 password !s3cret
```

--------------------------------

### Example Git Commit Sign-off

Source: https://github.com/sassoftware/python-swat/blob/main/ContributorAgreement.txt

An example of a correctly formatted sign-off line for a Git commit message.

```git
Signed-off-by: Random J. Developer <random@developer.example.org>
```

--------------------------------

### Connect to CAS using a URL with Proxy

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

This example shows how to connect to CAS using a URL when a proxy server is involved, requiring a base path. Username and password must be specified as keyword arguments.

```python
import swat

s = swat.CAS(url='http://dssgwnlt.unx.sas.com:8777/casmanagement', path='/cas-shared-default-http', username='casadmin', password='password')
```

--------------------------------

### Example AI Contribution Disclosure (Assisted)

Source: https://github.com/sassoftware/python-swat/blob/main/ContributorAgreement.txt

An example of the 'Assisted-by' line for a commit message where an AI tool assisted in the contribution.

```git
Assisted-by: GitHub Copilot
```

--------------------------------

### Example AI Contribution Disclosure (Entirely Generated)

Source: https://github.com/sassoftware/python-swat/blob/main/ContributorAgreement.txt

An example of the 'Generated-by' line for a commit message where the contribution was entirely created by an AI.

```git
Generated-by: Claude Code
```

--------------------------------

### Read CSV and Get Table Head

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/workflows.md

Reads a CSV file into a CAS table and displays the first few rows using pandas-DataFrame methods. This demonstrates the basic workflow of loading data and interacting with it as a CASTable object.

```python
from swat import CAS

# Connect to CAS
conn = CAS(host='cas.example.com', port=5570, username='user', password='password')

# Read a CSV file into a CAS table
# The 'table' parameter is automatically populated with the CASTable object
# The 'head()' method is a pandas.DataFrame method applied to the CASTable object
table = conn.read_csv('mydata.csv')

# Display the first 5 rows of the CAS table
print(table.head())

# Close the connection
conn.terminate()
```

--------------------------------

### Set CASSPN environment variable for Kerberos

Source: https://github.com/sassoftware/python-swat/blob/main/README.md

For SAS Viya 3.5 CAS servers using Kerberos with python-swat v1.8.0+, set the CASSPN environment variable before connecting. The SPN must start with 'sascas@' followed by the hostname.

```bash
export CASSPN=sascas@host
```

--------------------------------

### Resolve Unable to Import _pyXXswat Error

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/troubleshooting.md

If you receive a 'ValueError: Could not import import _pyXXswat.' when creating a CAS connection, it typically indicates missing SAS TK libraries or an improperly installed Python extension. Ensure you are using the installer that bundles SAS TK libraries or, if using a source-only installation, connect to the REST interface of CAS instead of a binary port.

```python
In [1]: conn = swat.CAS(hostname, port)

. . .

During handling of the above exception, another exception occurred:

ValueError                                Traceback (most recent call last)
<ipython-input-2-cb8d2ab92685> in <module>()
----> 1 swat.CAS('my-cas', 12345)

connection.py in __init__(self, hostname, port, username, password, session,
                          locale, nworkers, name, authinfo, protocol, **kwargs)
    223                 self._sw_error = rest.REST_CASError(a2n(soptions))
    224             else:
--> 225                 self._sw_error = clib.SW_CASError(a2n(soptions))
    226         except SystemError:
    227             raise SWATError('Could not create CAS object. Check your TK path setting.')

clib.py in SW_CASError(*args, **kwargs)
     84     ''' Return a CASError (importing _pyswat as needed) '''
     85     if _pyswat is None:
---> 86         _import_pyswat()
     87     return _pyswat.SW_CASError(*args, **kwargs)
     88

clib.py in _import_pyswat()
     43         raise ValueError(('Could not import import %s.  This is likely due to an ' 
     44                           'incorrect SAS TK path or an error while loading the SAS TK subsystem. ' 
---> 45                           'You can try using the REST interface as an alternative.') % libname)
     46 
     47 

ValueError: Could not import import _py34swat.  This is likely due to an incorrect SAS TK
            path or an error while loading the SAS TK subsystem.  You can try using the
            REST interface as an alternative.
```

--------------------------------

### Python SWAT Missing Linux Library Dependency

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/troubleshooting.md

This error indicates that a required shared library for SWAT is missing on the Linux system. It often appears during CAS connection attempts. Installing the missing package or setting LD_LIBRARY_PATH can resolve this.

```python
In [1]: conn = swat.CAS(hostname, port)
tkBoot failed:  Cannot dlopen [tkmk.so] : [libnuma.so.1: cannot open shared object file: No such file or directory]
```

--------------------------------

### Running Individual SWAT Test with Profiling

Source: https://github.com/sassoftware/python-swat/blob/main/CONTRIBUTING.md

Run a specific test file, such as test_basics.py, and enable profiling to analyze its performance. This is useful for debugging and optimization.

```bash
python swat/tests/cas/test_basics.py --profile
```

--------------------------------

### Connect to CAS Server and Execute Server Status Action

Source: https://github.com/sassoftware/python-swat/blob/main/README.md

Import the swat library, establish a connection to the CAS server, execute the serverstatus action, print the output, and close the connection. The default port is 5570.

```python
>>> import swat
>>> conn = swat.CAS(host, port, username, password)
>>> out = conn.serverstatus()
NOTE: Grid node action status report: 1 nodes, 6 total actions executed.
>>> print(out)
    [About]
    
     {'CAS': 'Cloud Analytic Services',
      'Copyright': 'Copyright © 2014-2016 SAS Institute Inc. All Rights Reserved.',
      'System': {'Hostname': 'cas01',
       'Model Number': 'x86_64',
       'OS Family': 'LIN X64',
       'OS Name': 'Linux',
       'OS Release': '2.6.32-504.12.2.el6.x86_64',
       'OS Version': '#1 SMP Sun Feb 1 12:14:02 EST 2015'},
      'Version': '3.01',
      'VersionLong': 'V.03.01M0D08232016',
      'license': {'expires': '20Oct2016:00:00:00',
       'gracePeriod': 62,
       'site': 'SAS Institute Inc.',
       'siteNum': 1,
       'warningPeriod': 31}}
    
    [server]
    
     Server Status
    
        nodes  actions
     0      1        6
    
    [nodestatus]
    
     Node Status
    
         name        role  uptime  running  stalled
     0  cas01  controller   4.836        0        0
    
    + Elapsed: 0.0168s, user: 0.016s, sys: 0.001s, mem: 0.287mb

    >>> conn.close()
```

--------------------------------

### Run Server Status Action

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Test your CAS connection by running the 'serverstatus' action. This action returns information about the CAS server.

```python
s.serverstatus()
```

--------------------------------

### Running SWAT Tests with nosetests

Source: https://github.com/sassoftware/python-swat/blob/main/CONTRIBUTING.md

Execute the entire SWAT test suite using the nosetests command. Ensure your environment variables are set for CAS connection.

```bash
nosetests -v swat.tests
```

--------------------------------

### Connect to CAS using Hostname and Port

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Use this method to establish a connection to a CAS server by providing the hostname, port, username, and password.

```python
import swat

s = swat.CAS('dssgwnlt.unx.sas.com', 8777, 'casadmin', 'password')
```

--------------------------------

### Setting File Permissions

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Command to set the necessary file permissions for the authinfo file, ensuring it is only readable and writable by the owner. This is crucial for security.

```default
chmod 0600 ~/.authinfo
```

--------------------------------

### Call CAS Action with Response Callback

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/workflows.md

Demonstrates calling a CAS action ('summary') and processing its entire response using a response callback function. The callback function receives the response, connection, and user data.

```python
from swat import CAS

def my_response_callback(response, connection, userdata):
    print(f"Response Keys: {list(response.keys())}")
    print(f"Userdata: {userdata}")
    # Return updated userdata for the next call
    return userdata + 1

# Connect to CAS
conn = CAS(host='cas.example.com', port=5570, username='user', password='password')

# Load the 'simple' action set
conn.loadactionset('simple')

# Call the 'summary' action with a response callback
# The initial userdata is 0
results = conn.simple.summary(table='mydata', responsefunc=my_response_callback, userdata=0)

# Close the connection
conn.terminate()
```

--------------------------------

### Basic .casrc Configuration

Source: https://github.com/sassoftware/python-swat/blob/main/CONTRIBUTING.md

This is the most basic form of a .casrc configuration file. It specifies the CAS host, port, and protocol.

```lua
cashost = 'myhost.com'
casport = 5570
casprotocol = 'cas'
```

--------------------------------

### OAuth Token with PKCE

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Enables Proof Key for Code Exchange (PKCE) for obtaining OAuth tokens via authentication codes, enhancing security for HTTP connections. Requires Python 3.6+. Set pkce=True in the CAS constructor.

```python
from swat import CAS

# Authenticate using PKCE for OAuth token generation
c = CAS(hostname='cas.my-company.com', pkce=True)

# Alternatively, use the environment variable CAS_PKCE or VIYA_PKCE
# c = CAS(hostname='cas.my-company.com', pkce=True)

```

--------------------------------

### Call CAS Action with Response Callback

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/workflows.md

Demonstrates calling a CAS action ('summary') and processing its response using a result callback function. The callback function receives the result key, value, response, connection, and user data.

```python
from swat import CAS

def my_result_callback(key, value, response, connection, userdata):
    print(f"Result Key: {key}")
    print(f"Result Value: {value}")
    print(f"Userdata: {userdata}")
    # Return updated userdata for the next call
    return userdata + 1

# Connect to CAS
conn = CAS(host='cas.example.com', port=5570, username='user', password='password')

# Load the 'simple' action set
conn.loadactionset('simple')

# Call the 'summary' action with a result callback
# The initial userdata is 0
results = conn.simple.summary(table='mydata', resultfunc=my_result_callback, userdata=0)

# Close the connection
conn.terminate()
```

--------------------------------

### Authinfo File Format

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Defines the structure for storing host, user, password, and port information in an authinfo file. This method is recommended for managing credentials securely.

```default
host HOST user USERNAME password PASSWORD port PORT
```

--------------------------------

### CAS Action Call with Mixed Case Parameters

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/gotchas.md

Demonstrates how mixed-case parameter keys in a CAS action call can lead to errors due to duplicate key interpretation by CAS. The SWAT client typically lower-cases parameter names to avoid this.

```python
conn.summary(subset=['Max', 'Min']
             subSet=['N'])
```

--------------------------------

### OAuth Token Authentication

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Demonstrates how to authenticate to the CAS server using an OAuth token. The token can be provided directly in the CAS constructor via the 'password' parameter, or through environment variables.

```python
from swat import CAS

# Authenticate using OAuth token via password parameter
c = CAS(hostname='cas.my-company.com', password='YOUR_OAUTH_TOKEN')

# Authenticate using OAuth token via environment variable (CAS_TOKEN or CAS_PASSWORD)
# Ensure the environment variable is set before running the script
# c = CAS(hostname='cas.my-company.com')

```

--------------------------------

### Kerberos Authentication Configuration

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Explains how to configure Kerberos authentication for Viya 4 CAS servers. For Viya 3.5 compatibility with SWAT releases 1.8.0+, use the CASSPN environment variable to specify the Viya 3.5 service principal name.

```bash
# For Viya 3.5 CAS servers with SWAT 1.8.0+
export CASSPN="sascas@your_viya3.5_hostname.com"

```

--------------------------------

### Connect to CAS using a URL

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Connect to a CAS server using a URL, which is useful for REST connections. Username and password must be specified as keyword arguments.

```python
import swat

s = swat.CAS(url='http://dssgwnlt.unx.sas.com:8777/casmanagement', username='casadmin', password='password')
```

--------------------------------

### Fix Incorrect SAS TK Configuration

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/troubleshooting.md

If you encounter a 'tkBoot failed' or 'Could not create CAS object. Check your TK path setting.' error, ensure that `swat.options.tkpath` is correctly set to the location of the SAS TK libraries.

```python
In [1]: conn = swat.CAS(hostname, port)
tkBoot failed:  Cannot Locate [tkmk] in [/usr/local/lib/swat-tk:/opt/sas/viya/SASFoundation/sasexe/:
Could not get TK handle
---------------------------------------------------------------------------

. . .

SWATError                                 Traceback (most recent call last)
<ipython-input-2-d18c0dfd66ee> in <module>()
----> 1 s = swat.CAS('my-cas', 12345)

connection.py in __init__(self, hostname, port, username, password, session,
                          locale, nworkers, name, authinfo, protocol, **kwargs)
    225                 self._sw_error = clib.SW_CASError(a2n(soptions))
    226         except SystemError:
--> 227             raise SWATError('Could not create CAS object. Check your TK path setting.')
    228
    229         # Make the connection

SWATError: Could not create CAS object. Check your TK path setting.
```

--------------------------------

### Troubleshooting: Unable to Locate libssl Error

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/encryption.md

Indicates that the client cannot find the libssl shared library on the system, often seen on Ubuntu Linux. This requires specifying the path to the libssl file.

```text
ERROR: The TCP/IP negClientSSL support routine failed with status 803fd068
```

--------------------------------

### Set CAS Client SSL CA List Environment Variable

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/encryption.md

Configure the path to the SSL certificate bundle on the client side for Linux, Mac, and REST protocol on Windows. This variable must be set in the environment where the Python client is running.

```shell
CAS_CLIENT_SSL_CA_LIST='/path/to/certificates.pem'
```

--------------------------------

### Python SWAT Authentication Error: Incorrect Permissions

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/troubleshooting.md

This snippet illustrates an authentication error due to incorrect file permissions on the Authinfo file. The file must be readable only by the owner.

```python
In [1]: conn = swat.CAS('my-cas', 12345)
WARNING: Incorrect permissions on netrc/authinfo file.
ERROR: Kerberos initialization failed. Your credential cache is either expired or missing.
---------------------------------------------------------------------------
SystemError                               Traceback (most recent call last)
connection.py in__init__(self, hostname, port, username, password, session,
                         locale, nworkers, name, authinfo, protocol, **kwargs)
    256                                                                 a2n(soptions),
--> 257                                                                 self._sw_error)
    258                 if self._sw_connection is None:

. .

SWATError: Could not connect to 'my-cas' on port 12345.
```

--------------------------------

### Create Custom Data Loader with CASDataMsgHandler

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/loading-data.md

Implement a custom data loader by subclassing CASDataMsgHandler. This allows uploading data from any Python-readable stream or file. Requires defining 'vars' and implementing 'getrow()'.

```python
from swat.cas.datamsghandlers import CASDataMsgHandler

class MyDataMsgHandler(CASDataMsgHandler):
    def __init__(self, data, **kwargs):
        super().__init__(**kwargs)
        self.data = data
        self.row_index = 0
        self.vars = {
            "col1": "char",
            "col2": "int",
            "col3": "double"
        }

    def getrow(self):
        if self.row_index >= len(self.data):
            return None
        row = self.data[self.row_index]
        self.row_index += 1
        return row

# Example usage:
data = [
    ["a", 1, 1.1],
    ["b", 2, 2.2],
    ["c", 3, 3.3]
]

my_dmh = MyDataMsgHandler(data)

sess.addtable(my_dmh, casout={'name': 'custom_data'})

```

--------------------------------

### Upload and Parse File using CAS.upload_file()

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/loading-data.md

Upload a data file to CAS and parse it on the server. This method is generally faster for larger datasets than client-side parsing.

```python
from swat import CAS
c = CAS(host='cas-shared-default-cascontroller.cas.svc', port=8765)

# Upload and parse a file from a URL
sess.upload_file('https://raw.githubusercontent.com/sassoftware/python-swat/main/samples/data/cars.csv', casout={'name': 'cars_uploaded'})

# Upload and parse a local file
# sess.upload_file('cars.csv', casout={'name': 'cars_uploaded'})
```

--------------------------------

### OAuth Token via Authentication Code

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Shows how to obtain an OAuth token using an authentication code when using the HTTP protocol. The 'authcode' parameter in the CAS constructor is used for this purpose.

```python
from swat import CAS

# Authenticate using an authentication code
c = CAS(hostname='cas.my-company.com', authcode='YOUR_AUTH_CODE')

# Alternatively, use the environment variable CAS_AUTHCODE or VIYA_AUTHCODE
# c = CAS(hostname='cas.my-company.com')

```

--------------------------------

### Converting CASTable to DataFrame

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/table-vs-dataframe.md

Demonstrates how to convert a CASTable object to a pandas DataFrame. Be cautious as this method attempts to pull all data locally, regardless of size.

```python
tbl.to_frame()
# Warning: This will attempt to pull all data down regardless of size.
```

--------------------------------

### Troubleshooting: No Certificate Used Error

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/encryption.md

Displays the error message when attempting to connect to an SSL-enabled CAS server without a configured client certificate. This typically indicates that the CAS_CLIENT_SSL_CA_LIST environment variable is not set correctly.

```text
ERROR: The TCP/IP negClientSSL support routine failed with status 807ff013.
```

--------------------------------

### CASTable Method Return Types

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/table-vs-dataframe.md

Illustrates the return types for common methods when operating on CASTable objects compared to pandas DataFrames. Note that CAS actions like summary() return CASResults.

```python
o.head()
# Returns: DataFrame
o.describe()
# Returns: DataFrame
o['col']
# Returns: CASColumn
o[['col']]
# Returns: CASTable
o.summary()
# Returns: CASResults
```

--------------------------------

### Invoke Multiple CAS Actions Simultaneously

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/workflows.md

Invokes multiple CAS actions ('summary') on different tables across two connections concurrently. Responses are retrieved iteratively using getnext(), allowing for parallel processing.

```python
from swat import CAS

# Connect to two CAS instances
conn1 = CAS(host='cas1.example.com', port=5570, username='user', password='password')
conn2 = CAS(host='cas2.example.com', port=5570, username='user', password='password')

# Load the 'simple' action set on both connections
conn1.loadactionset('simple')
conn2.loadactionset('simple')

# Invoke the 'summary' action on different tables from both connections
# Note: The 'table' parameter is specified for each action
results1 = conn1.simple.summary(table='table1', invoke=True)
results2 = conn2.simple.summary(table='table2', invoke=True)

# Iterate over the connection objects to retrieve responses as they become available
# This allows for handling responses from multiple actions concurrently
for result in conn1.getnext():
    print(result)
for result in conn2.getnext():
    print(result)

# Close the connections
conn1.terminate()
conn2.terminate()
```

--------------------------------

### Set TKESSL_OPENSSL_LIB Environment Variable

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/encryption.md

Specify the path to the libssl shared library on the client side when it cannot be located automatically. This is a common solution for 'Unable to Locate libssl' errors on Linux systems.

```shell
TKESSL_OPENSSL_LIB=/path/to/libs/libssl.so.1.0.0
```

--------------------------------

### Uploading DataFrame to CAS

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/table-vs-dataframe.md

Shows how to upload a pandas DataFrame to a CAS table. This is a way to make local DataFrame data available on the CAS server.

```python
cas.upload(df=my_dataframe, casout=my_cas_table)
```

--------------------------------

### Load CSV Data using CAS.read_csv()

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/loading-data.md

Load data from a CSV file or URL into a CAS table using a method similar to pandas.read_csv(). This is suitable for smaller datasets.

```python
from swat import CAS
c = CAS(host='cas-shared-default-cascontroller.cas.svc', port=8765)

# Load data from a URL
sess.read_csv('https://raw.githubusercontent.com/sassoftware/python-swat/main/samples/data/cars.csv')

# Load data from a local file
# sess.read_csv('cars.csv')
```

--------------------------------

### Access CAS Action Results by Key

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Access the results of a CAS action using standard dictionary key access. The keys are displayed in square brackets in the output.

```python
results = s.serverstatus()
print(results['About'])
print(results['server'])
print(results['nodestatus'])
```

--------------------------------

### CASColumn vs. Series Method Return Types

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/table-vs-dataframe.md

Shows the return types for common methods when operating on CASColumn objects compared to pandas Series. CASColumn operates on a single column of data.

```python
c.head()
# Returns: Series
c[c.col > 1]
# Returns: CASColumn
```

--------------------------------

### Python SWAT Authentication Error: Incorrect Password

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/troubleshooting.md

This snippet shows an authentication error resulting from an incorrect password in the Authinfo file or a mismatch between the hostname/port in the file and the CAS constructor.

```python
In [1]: conn = swat.CAS('my-cas', 12345)
ERROR: Connection failed. Server returned: Authentication failed: Access denied.
---------------------------------------------------------------------------
SystemError                               Traceback (most recent call last)
connection.py in __init__(self, hostname, port, username, password, session,
                          locale, nworkers, name, authinfo, protocol, **kwargs)
    256                                                                 a2n(soptions),
--> 257                                                                 self._sw_error)
    258                 if self._sw_connection is None:

. .

SWATError: Could not connect to 'my-cas' on port 12345.
```

--------------------------------

### Sign-off for Git Commit Messages

Source: https://github.com/sassoftware/python-swat/blob/main/ContributorAgreement.txt

Include this line in your commit message to attest to your right to contribute. Use your real name.

```git
Signed-off-by: Firstname Lastname <user@domain>
```

--------------------------------

### Python SWAT Refused Connection Error

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/troubleshooting.md

This snippet shows the error message and traceback when a connection to the CAS server is refused. This typically indicates the CAS server is not running or is inaccessible due to network issues.

```python
In [1]: conn = swat.CAS('my-cas', 12345)
ERROR: The TCP/IP tcpSockConnect support routine failed with error 61 (The connection was refused.).
ERROR: Failed to connect to host 'my-cas', port 12345.

. .

During handling of the above exception, another exception occurred:

SWATError                                 Traceback (most recent call last)
<ipython-input-3-404a7919d58a> in <module>()
----> 1 conn = swat.CAS('my-cas', 12345)

cas/connection.py in __init__(self, hostname, port, username, password, session,
                              locale, nworkers, name, authinfo, protocol, **kwargs)
    259                     raise SystemError
    260         except SystemError:
--> 261             raise SWATError(self._sw_error.getLastErrorMessage())
    262
    263         errorcheck(self._sw_connection.setZeroIndexedParameters(), self._sw_connection)

SWATError: Could not connect to 'my-cas' on port 12345.
```

--------------------------------

### Set LD_LIBRARY_PATH Environment Variable

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/encryption.md

An alternative method to resolve 'Unable to Locate libssl' errors by setting the general library path environment variable. This helps the system find shared libraries, including libssl.

```shell
LD_LIBRARY_PATH=/path/to/libs
```

--------------------------------

### Update ALWAYS_INLINE Definition for Intel Compiler on Windows

Source: https://github.com/sassoftware/python-swat/blob/main/swat/readme.md

This change was made to the `pyport.h` file to resolve a compiler error when using the Intel compiler on Windows. It ensures correct handling of the `ALWAYS_INLINE` macro.

```c
#elif defined(__GNUC__) || defined(__clang__) || defined(__INTEL_COMPILER)
```

```c
#elif defined(__GNUC__) || defined(__clang__) || defined(__INTEL_LLVM_COMPILER) || (defined(__INTEL_COMPILER) && !defined(_WIN32))
```

--------------------------------

### Troubleshooting: Incorrect Certificate Used Error

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/encryption.md

Displays the error message when the client is using an incorrect SSL certificate for the CAS server. This suggests that the CAS_CLIENT_SSL_CA_LIST environment variable points to the wrong certificate file.

```text
ERROR: The TCP/IP negClientSSL support routine failed with status 807ff008.
```

--------------------------------

### Calling CAS Action with Capitalized Name

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/gotchas.md

Shows how capitalizing the first letter of a CAS action name, like 'conn.Summary()', returns a CAS action object instead of executing the action. This enables building action parameters in an object-oriented manner.

```python
conn.Summary()
```

--------------------------------

### AI Contribution Disclosure (Assisted)

Source: https://github.com/sassoftware/python-swat/blob/main/ContributorAgreement.txt

Add this line to your commit message if an AI tool assisted in creating your contribution. Specify the assistant's name.

```git
Assisted-by: Assistant Name
```

--------------------------------

### Access CAS Action Results by Attribute

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/getting-started.md

Access the results of a CAS action using attribute notation for convenience. Be aware of potential naming collisions with Python attributes.

```python
results = s.serverstatus()
print(results.About)
print(results.server)
print(results.nodestatus)
```

--------------------------------

### AI Contribution Disclosure (Entirely Generated)

Source: https://github.com/sassoftware/python-swat/blob/main/ContributorAgreement.txt

Add this line to your commit message if an AI tool generated your entire contribution. Specify the assistant's name.

```git
Generated-by: Assistant Name
```

--------------------------------

### Accessing CAS Action with Explicit Namespace

Source: https://github.com/sassoftware/python-swat/blob/main/doc/source/gotchas.md

Demonstrates how to explicitly access a CAS action using its action set name to avoid attribute collisions on CASTable objects. This ensures you are calling the intended CAS action rather than a Python method or table parameter.

```python
simple.groupby(name='mycas.iris', groupby='species')
```