### Install aranyasen/hl7 Package

Source: https://github.com/senaranya/hl7/blob/master/README.md

Use Composer to install the HL7 package.

```bash
composer require aranyasen/hl7
```

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

### NK1::setStartDate

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/NK1.md

Sets the start date for the NK1 segment.

```APIDOC
## NK1::setStartDate

### Description
Sets the start date for the NK1 segment.

### Method
This information is not available in the provided text.

### Endpoint
This information is not available in the provided text.

### Parameters
This function has no parameters.

### Request Example
This information is not available in the provided text.

### Response
#### Success Response (200)
`void`

#### Response Example
This information is not available in the provided text.
```

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

### TQ1::setStartDateTime

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/TQ1.md

Sets the start date and time for the TQ1 segment.

```APIDOC
## TQ1::setStartDateTime

### Description
Sets the start date and time for the TQ1 segment.

### Method
Not specified (likely a setter method within a class)

### Endpoint
Not applicable (method within a class)

### Parameters
This function has no parameters.

### Response
#### Success Response (void)
void

### Response Example
void
```

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

### NK1::getStartDate

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/NK1.md

Retrieves the start date associated with the NK1 segment.

```APIDOC
## NK1::getStartDate

### Description
Retrieves the start date associated with the NK1 segment.

### Method
GET (assumed, as it's a getter method)

### Endpoint
/senaranya/hl7/NK1/getStartDate

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **Return Value** (void) - Indicates the function does not return a specific value, but may perform an action or set a state.
```

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

### HL7 PV2 Get Methods

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/PV2.md

This section details the GET methods available for retrieving specific data points from the HL7 PV2 segment.

```APIDOC
## HL7 PV2 Get Endpoints

### Description
These endpoints allow retrieval of specific data fields from the HL7 PV2 segment.

### Methods
GET

### Endpoints
- /senaranya/hl7/pv2/accommodationCode
- /senaranya/hl7/pv2/actualLengthOfInpatientStay
- /senaranya/hl7/pv2/admissionLevelOfCareCode
- /senaranya/hl7/pv2/admitReason
- /senaranya/hl7/pv2/advanceDirectiveCode
- /senaranya/hl7/pv2/babyDetainedIndicator
- /senaranya/hl7/pv2/billingMediaCode
- /senaranya/hl7/pv2/clinicOrganizationName
- /senaranya/hl7/pv2/employmentIllnessRelatedIndicator
- /senaranya/hl7/pv2/estimatedLengthofInpatientStay
- /senaranya/hl7/pv2/expectedAdmitDateTime
- /senaranya/hl7/pv2/expectedDischargeDateTime
- /senaranya/hl7/pv2/expectedDischargeDisposition
- /senaranya/hl7/pv2/expectedLOAReturnDateTime
- /senaranya/hl7/pv2/expectedNumberOfInsurancePlans
- /senaranya/hl7/pv2/expectedSurgeryDateAndTime
- /senaranya/hl7/pv2/firstSimilarIllnessDate
- /senaranya/hl7/pv2/livingWillCode
- /senaranya/hl7/pv2/militaryNonAvailabilityCode
- /senaranya/hl7/pv2/militaryPartnershipCode
- /senaranya/hl7/pv2/modeOfArrivalCode
- /senaranya/hl7/pv2/newbornBabyIndicator
- /senaranya/hl7/pv2/organDonorCode
- /senaranya/hl7/pv2/patientChargeAdjustmentCode
- /senaranya/hl7/pv2/patientConditionCode
- /senaranya/hl7/pv2/patientStatusCode
- /senaranya/hl7/pv2/patientStatusEffectiveDate
- /senaranya/hl7/pv2/patientValuables
- /senaranya/hl7/pv2/patientValuablesLocation
- /senaranya/hl7/pv2/precautionCode
- /senaranya/hl7/pv2/previousServiceDate
- /senaranya/hl7/pv2/previousTreatmentDate
- /senaranya/hl7/pv2/purgeStatusCode
- /senaranya/hl7/pv2/purgeStatusDate
- /senaranya/hl7/pv2/recreationalDrugUseCode
- /senaranya/hl7/pv2/recurringServiceCode
- /senaranya/hl7/pv2/referralSourceCode
- /senaranya/hl7/pv2/retentionIndicator
- /senaranya/hl7/pv2/signatureOnFileDate
- /senaranya/hl7/pv2/specialProgramCode
- /senaranya/hl7/pv2/transferReason
- /senaranya/hl7/pv2/visitDescription
- /senaranya/hl7/pv2/visitPriorityCode
- /senaranya/hl7/pv2/visitProtectionIndicator
- /senaranya/hl7/pv2/visitPublicityCode
- /senaranya/hl7/pv2/visitUserCode

### Parameters
None

### Request Example
GET /senaranya/hl7/pv2/patientStatusCode

### Response
#### Success Response (200)
- **statusCode** (string) - The patient status code.

#### Response Example
{
  "statusCode": "A"
}
```

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

### AIG::setStartDateTime

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIG.md

Sets the start date-time.

```APIDOC
## AIG::setStartDateTime

### Description
Sets the start date-time.

### Method
POST (assumed, as it modifies state)

### Endpoint
/senaranya/hl7/AIG/setStartDateTime

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **void** (void) - Indicates no specific return value or type.
```

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

### Get Pre-Certification Requirement - IN3::getPreCertificationRequirement

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves the pre-certification requirement. This function takes no parameters and returns void.

```php
getPreCertificationRequirement (void)
```

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

### MSH Segment Usage

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/MSH.md

Example of how to instantiate and use the MSH segment class.

```APIDOC
## MSH Segment Usage

### Description
This code snippet demonstrates the basic instantiation and usage of the MSH segment class.

### Code Example
```php
$seg = new MSH();

$seg->setField(9, "ADT^A24");
echo $seg->getField(1);
```

### Notes
The MSH segment has a unique structure where the first field is the field separator. Field indexing starts from 1 for the field separator and 2 for subsequent fields.
```

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

### AIG::getStartDateTimeOffset

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIG.md

Retrieves the start date-time offset.

```APIDOC
## AIG::getStartDateTimeOffset

### Description
Retrieves the start date-time offset.

### Method
GET (assumed, as it's a getter method)

### Endpoint
/senaranya/hl7/AIG/getStartDateTimeOffset

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **void** (void) - Indicates no specific return value or type.
```

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

### AIP::setStartDateTime

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIP.md

Sets the start date and time for the segment.

```APIDOC
## AIP::setStartDateTime

### Description
Sets the start date and time.

### Method
`static`

### Endpoint
N/A (Method call)

### Parameters
This function has no parameters.

### Response
#### Success Response (void)
Returns void.

### Request Example
```php
AIP::setStartDateTime();
```

### Response Example
```
void
```
```

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

### AIG::getStartDateTimeOffsetUnits

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIG.md

Retrieves the units for the start date-time offset.

```APIDOC
## AIG::getStartDateTimeOffsetUnits

### Description
Retrieves the units for the start date-time offset.

### Method
GET (assumed, as it's a getter method)

### Endpoint
/senaranya/hl7/AIG/getStartDateTimeOffsetUnits

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **void** (void) - Indicates no specific return value or type.
```

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

### AIL::setStartDateTime

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIL.md

Sets the start date-time for the segment.

```APIDOC
## AIL::setStartDateTime

### Description
Sets the start date-time for the segment.

### Method
`setStartDateTime (void)`

### Endpoint
N/A (Class method)

### Parameters
This function has no parameters.

### Return Values
`void`
```

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

### AIP::setStartDateTimeOffsetUnits

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIP.md

Sets the units for the start date and time offset.

```APIDOC
## AIP::setStartDateTimeOffsetUnits

### Description
Sets the units for the start date and time offset.

### Method
`static`

### Endpoint
N/A (Method call)

### Parameters
This function has no parameters.

### Response
#### Success Response (void)
Returns void.

### Request Example
```php
AIP::setStartDateTimeOffsetUnits();
```

### Response Example
```
void
```
```

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

### AIL::setStartDateTimeOffsetUnits

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIL.md

Sets the units for the start date-time offset.

```APIDOC
## AIL::setStartDateTimeOffsetUnits

### Description
Sets the units for the start date-time offset.

### Method
`setStartDateTimeOffsetUnits (void)`

### Endpoint
N/A (Class method)

### Parameters
This function has no parameters.

### Return Values
`void`
```

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

### Get Penalty - IN3::getPenalty

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves penalty information. This function takes no parameters and returns void.

```php
getPenalty (void)
```

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

### Create and Set PID Segment Data

Source: https://context7.com/senaranya/hl7/llms.txt

Demonstrates creating a new PID segment and setting various patient identification and demographic fields using setter methods. Includes examples for patient identifiers, names, birth date, sex, race, marital status, address, and phone numbers.

```php
<?php
use Aranyasen\HL7;
use Aranyasen\HL7\Segments\PID;

// Create a new PID segment (auto-increments Set ID)
$pid = new PID();

// Set patient identification
$pid->setPatientIdentifierList(['12345678', '', '', 'Hospital', 'MR']);  // MRN
$pid->setPatientID('EXT-001');            // External ID (PID.2)
$pid->setAlternatePatientID('ALT-001');   // Alternate ID (PID.4)

// Set patient name (Last^First^Middle^Suffix^Prefix)
$pid->setPatientName(['Doe', 'John', 'Michael', 'Jr', 'Dr']);

// Set demographics
$pid->setDateTimeOfBirth('19800515120000');  // YYYYMMDDHHMMSS
$pid->setSex('M');                            // M, F, O, U, A, N (validated)
$pid->setRace('2106-3');                      // Race code
$pid->setEthnicGroup('2186-5');               // Ethnicity code
$pid->setMaritalStatus('M');                  // Marital status
$pid->setReligion('CHR');                     // Religion code
$pid->setCitizenship('USA');
$pid->setNationality('USA');

// Set contact information
$pid->setPatientAddress(['123 Main St', 'Apt 4B', 'New York', 'NY', '10001', 'USA']);
$pid->setPhoneNumberHome('555-123-4567');
$pid->setPhoneNumberBusiness('555-987-6543');
$pid->setPrimaryLanguage('EN');

// Set identifiers
$pid->setSSNNumber('123-45-6789');
$pid->setDriversLicenseNumber(['D1234567', 'NY']);
$pid->setPatientAccountNumber('ACCT001');

// Get patient information
$name = $pid->getPatientName();              // ['Doe', 'John', 'Michael', 'Jr', 'Dr']
$dob = $pid->getDateTimeOfBirth();           // '19800515120000'
$sex = $pid->getSex();                       // 'M'
$address = $pid->getPatientAddress();
$mrn = $pid->getPatientIdentifierList();

// Parse existing PID segment
$hl7String = "MSH|^~\\&|||||||ADT^A01||P|2.3|\r" .
             "PID|1||123456^^^HospA^MR~987654^^^SSA^SS||Smith^Jane^Marie||19901220|F|||456 Oak Ave^^Boston^MA^02101||617-555-0123|||M||ACC789|\r";

$message = HL7::from($hl7String)->keepEmptySubfields()->create();
$pid = $message->getFirstSegmentInstance('PID');

echo $pid->getID();                          // 1
print_r($pid->getPatientIdentifierList());   // Multiple IDs with repetition separator
echo $pid->getPatientName()[0];              // 'Smith'
echo $pid->getSex();                         // 'F'
echo $pid->getMaritalStatus();               // 'M'

// Reset PID index for new batch
PID::resetIndex(1);

```

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

### Get Days - IN3::getDays

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves the number of days. This function takes no parameters and returns void.

```php
getDays (void)
```

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

### Get Second Opinion Documentation Received - IN3::getSecondOpinionDocumentationReceived

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Checks if second opinion documentation has been received. This function takes no parameters and returns void.

```php
getSecondOpinionDocumentationReceived (void)
```

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

### Get HL7 Version

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/MSH.md

Retrieve the HL7 version of the message from the MSH segment. Examples include 2.1, 2.3, or 3.0.

```php
public getVersionId (void)
```

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

### MSH::setReceivingApplication

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/MSH.md

This function has no parameters and returns void.

```php
setReceivingApplication (void)
```

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

### Connection Constructor

Source: https://github.com/senaranya/hl7/blob/master/docs/Connection.md

Establishes a TCP connection to an HL7 server. Throws an exception if the connection fails.

```APIDOC
## Connection::__construct

### Description
Creates a connection to a HL7 server, or throws exception when a connection could not be established.

### Method
CONSTRUCTOR

### Parameters
#### Path Parameters
- **host** (string) - Required - Host to connect to
- **port** (int) - Required - Port to connect to
- **timeout** (int) - Required - Connection timeout

### Response
#### Success Response (200)
- **void** - No return value

#### Throws Exceptions
- **\HL7ConnectionException**
```

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

### Get Multiple HL7 Segment Fields

Source: https://github.com/senaranya/hl7/blob/master/docs/Segment.md

Retrieve a range of fields from an HL7 segment. If only the start index is provided, all fields from that index to the end are returned. Returns an array of fields.

```php
$fields = $seg->getFields(2, 5);
```

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

### MSH::setSendingApplication

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/MSH.md

This function has no parameters and returns void.

```php
setSendingApplication (void)
```

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

### NK1 Segment Methods

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/NK1.md

This section lists the available methods for interacting with the NK1 segment, including methods for getting and setting various fields, as well as inherited methods from the base Segment class.

```APIDOC
## Methods

### Getters
- `getAddress()`
- `getAdministrativeSex()`
- `getAmbulatoryStatus()`
- `getBusinessPhoneNumber()`
- `getCitizenship()`
- `getContactPersonSocialSecurityNumber()`
- `getContactPersonsAddress()`
- `getContactPersonsName()`
- `getContactPersonsTelephoneNumber()`
- `getContactReason()`
- `getContactRole()`
- `getDateTimeOfBirth()`
- `getEndDate()`
- `getEthnicGroup()`
- `getHandicap()`
- `getID()`
- `getJobStatus()`
- `getLivingArrangement()`
- `getLivingDependency()`
- `getMaritalStatus()`
- `getMothersMaidenName()`
- `getNKName()`
- `getNationality()`
- `getNextOfKinBirthPlace()`
- `getNextOfKinOrAssociatedPartiesEmployeeNumber()`
- `getNextOfKinOrAssociatedPartiesJobCodeOrClass()`
- `getNextOfKinOrAssociatedPartiesJobTitle()`
- `getNextOfKinOrAssociatedPartysIdentifiers()`
- `getOrganizationName()`
- `getPhoneNumber()`
- `getPrimaryLanguage()`
- `getProtectionIndicator()`
- `getPublicityCode()`
- `getRace()`
- `getRelationship()`
- `getReligion()`
- `getStartDate()`
- `getStudentIndicator()`
- `getVipIndicator()`

### Setters
- `setAddress(address)`
- `setAdministrativeSex(sex)`
- `setAmbulatoryStatus(status)`
- `setBusinessPhoneNumber(number)`
- `setCitizenship(citizenship)`
- `setContactPersonSocialSecurityNumber(ssn)`
- `setContactPersonsAddress(address)`
- `setContactPersonsName(name)`
- `setContactPersonsTelephoneNumber(number)`
- `setContactReason(reason)`
- `setContactRole(role)`
- `setDateTimeOfBirth(datetime)`
- `setEndDate(date)`
- `setEthnicGroup(group)`
- `setHandicap(handicap)`
- `setID(id)`
- `setJobStatus(status)`
- `setLivingArrangement(arrangement)`
- `setLivingDependency(dependency)`
- `setMaritalStatus(status)`
- `setMothersMaidenName(name)`
- `setNKName(name)`
- `setNationality(nationality)`
- `setNextOfKinBirthPlace(place)`
- `setNextOfKinOrAssociatedPartiesEmployeeNumber(number)`
- `setNextOfKinOrAssociatedPartiesJobCodeOrClass(code)`
- `setNextOfKinOrAssociatedPartiesJobTitle(title)`
- `setNextOfKinOrAssociatedPartysIdentifiers(identifiers)`
- `setOrganizationName(name)`
- `setPhoneNumber(number)`
- `setPrimaryLanguage(language)`
- `setProtectionIndicator(indicator)`
- `setPublicityCode(code)`
- `setRace(race)`
- `setRelationship(relationship)`
- `setReligion(religion)`
- `setStartDate(date)`
- `setStudentIndicator(indicator)`
- `setVipIndicator(indicator)`

### Other Methods
- `__destruct()`
- `resetIndex()`: Reset index of this segment.

## Inherited Methods

### Constructor
- `__construct()`: Create a segment.

### Field Management
- `clearField(index)`: Remove any existing value from the field.
- `getField(index)`: Get the field at index.
- `getFields()`: Get fields from a segment.
- `setField(index, value)`: Set the field specified by index to value.

### Segment Information
- `getName()`: Get the name of the segment. This is basically the value at index 0.
- `size()`: Get the number of fields for this segment, not including the name.
```

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

### Set Certification Begin Date - IN3::setCertificationBeginDate

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Sets the certification begin date. This function takes no parameters and returns void.

```php
setCertificationBeginDate (void)
```

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

### EVN Segment Class Methods

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/EVN.md

This section details the methods available for interacting with the EVN segment, including getting and setting various event-related properties.

```APIDOC
## EVN::getDateTimePlannedEvent

### Description
Retrieves the planned date and time for the event.

### Method
GET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Returns void, but internally retrieves the planned event date/time.

### EVN::getEventOccurred

### Description
Retrieves the date and time when the event occurred.

### Method
GET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Returns void, but internally retrieves the event occurred date/time.

### EVN::getEventReasonCode

### Description
Retrieves the reason code for the event.

### Method
GET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Returns void, but internally retrieves the event reason code.

### EVN::getEventTypeCode

### Description
Retrieves the type code for the event.

### Method
GET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Returns void, but internally retrieves the event type code.

### EVN::getOperatorID

### Description
Retrieves the operator ID associated with the event.

### Method
GET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Returns void, but internally retrieves the operator ID.

### EVN::getRecordedDateTime

### Description
Retrieves the date and time when the event was recorded.

### Method
GET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Returns void, but internally retrieves the recorded date/time.

### EVN::setDateTimePlannedEvent

### Description
Sets the planned date and time for the event.

### Method
SET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Sets the planned event date/time.

### EVN::setEventOccurred

### Description
Sets the date and time when the event occurred.

### Method
SET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Sets the event occurred date/time.

### EVN::setEventReasonCode

### Description
Sets the reason code for the event.

### Method
SET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Sets the event reason code.

### EVN::setEventTypeCode

### Description
Sets the type code for the event.

### Method
SET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Sets the event type code.

### EVN::setOperatorID

### Description
Sets the operator ID associated with the event.

### Method
SET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Sets the operator ID.

### EVN::setRecordedDateTime

### Description
Sets the date and time when the event was recorded.

### Method
SET

### Endpoint
N/A (Method within a class)

### Parameters
`This function has no parameters.`

### Response
#### Success Response (void)
Sets the recorded date/time.
```

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

### SAC::getInitialSpecimenVolume

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/SAC.md

Retrieves the initial specimen volume. This function takes no parameters and returns void.

```php
getInitialSpecimenVolume (void)
```

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

### AIG::setStartDateTimeOffset

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIG.md

Sets the start date-time offset.

```APIDOC
## AIG::setStartDateTimeOffset

### Description
Sets the start date-time offset.

### Method
POST (assumed, as it modifies state)

### Endpoint
/senaranya/hl7/AIG/setStartDateTimeOffset

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **void** (void) - Indicates no specific return value or type.
```

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

### PV2::getVisitDescription

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/PV2.md

Retrieves the Visit Description.

```APIDOC
## PV2::getVisitDescription

### Description
Retrieves the Visit Description.

### Method
GET

### Endpoint
/senaranya/hl7/PV2/getVisitDescription

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **return_value** (void) - Description not specified.
```

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

### EQU::getEquipmentState

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/EQU.md

Retrieves the equipment state.

```APIDOC
### EQU::getEquipmentState

**Description**
```php
 getEquipmentState (void)
```

**Parameters**
`This function has no parameters.`

**Return Values**
`void`
```

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

### EQU::setEquipmentState

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/EQU.md

Sets the equipment state.

```APIDOC
### EQU::setEquipmentState

**Description**
```php
 setEquipmentState (void)
```

**Parameters**
`This function has no parameters.`

**Return Values**
`void`
```

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

### AIG::setStartDateTimeOffsetUnits

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIG.md

Sets the start date-time offset units.

```APIDOC
## AIG::setStartDateTimeOffsetUnits

### Description
Sets the start date-time offset units.

### Method
POST (assumed, as it modifies state)

### Endpoint
/senaranya/hl7/AIG/setStartDateTimeOffsetUnits

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **void** (void) - Indicates no specific return value or type.
```

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

### PV2::setVisitDescription

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/PV2.md

Sets the visit description. This method does not accept any parameters and returns void.

```APIDOC
## PV2::setVisitDescription

### Description
Sets the visit description.

### Method
This documentation does not specify the HTTP method as it appears to be a class method.

### Endpoint
This documentation does not specify an endpoint as it appears to be a class method.

### Parameters
This function has no parameters.

### Response
#### Success Response (void)
Returns void.

### Request Example
```php
PV2::setVisitDescription();
```

### Response Example
(void)
```

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

### HL7 Connection Constructor

Source: https://github.com/senaranya/hl7/blob/master/docs/Connection.md

Use the constructor to create a connection to a HL7 server. Specify the host, port, and an optional connection timeout. An exception is thrown if the connection cannot be established.

```php
public __construct (string $host, int $port, int $timeout)
```

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

### HL7 Factory for Message Creation (Deprecated Direct Instantiation)

Source: https://github.com/senaranya/hl7/blob/master/UPGRADE.md

Direct instantiation of Message is deprecated. Use the HL7 factory's `create()` method as an alternative to `createMessage()`. Refer to the README for detailed usage.

```php
$message = HL7::build()->create()
```

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

### AIL::setStartDateTimeOffset

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIL.md

Sets the start date-time offset for the segment.

```APIDOC
## AIL::setStartDateTimeOffset

### Description
Sets the start date-time offset for the segment.

### Method
`setStartDateTimeOffset (void)`

### Endpoint
N/A (Class method)

### Parameters
This function has no parameters.

### Return Values
`void`
```

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

### OBX::setEquipmentInstanceIdentifier

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/OBX.md

Sets the equipment instance identifier.

```APIDOC
## OBX::setEquipmentInstanceIdentifier

### Description
Sets the equipment instance identifier.

### Method
POST

### Endpoint
/senaranya/hl7/OBX/setEquipmentInstanceIdentifier

### Parameters
This function has no parameters.

### Request Body
- **identifier** (string) - The equipment instance identifier.

### Response
#### Success Response (200)
- **status** (void) - Indicates success or failure of setting the identifier.
```

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

### Create and Set OBX Segment Data

Source: https://context7.com/senaranya/hl7/llms.txt

Shows how to create OBX segments for different observation types (numeric and string) and set their properties like value type, identifier, value, units, and status. Also demonstrates building an ORU message and parsing OBX segments from an existing HL7 string.

```php
<?php
use Aranyasen\HL7;
use Aranyasen\HL7\Segments\OBX;

// Create observation result segments
$obx1 = new OBX();
$obx1->setValueType('NM');                                    // Numeric
$obx1->setObservationIdentifier(['2345-7', 'Glucose', 'LN']); // LOINC code
$obx1->setObservationSubId('1');
$obx1->setObservationValue('95');
$obx1->setUnits(['mg/dL', 'milligrams per deciliter']);
$obx1->setReferenceRange('70-100');
$obx1->setAbnormalFlags('N');                                 // Normal
$obx1->setObserveResultStatus('F');                           // Final

$obx2 = new OBX();
$obx2->setValueType('ST');                                    // String
$obx2->setObservationIdentifier(['8867-4', 'Heart Rate', 'LN']);
$obx2->setObservationValue('72');
$obx2->setUnits('bpm');
$obx2->setReferenceRange('60-100');
$obx2->setAbnormalFlags('N');
$obx2->setObserveResultStatus('F');
$obx2->setDateTimeOfTheObservation('20241215103045');
$obx2->setResponsibleObserver(['Smith', 'John', 'MD']);

// Build complete ORU message
$message = HL7::build()
    ->withHL7Version('2.5.1')
    ->create();

$msh = $message->getFirstSegmentInstance('MSH');
$msh->setMessageType('ORU');
$msh->setTriggerEvent('R01');
$msh->setSendingApplication('LabSystem');

$message->addSegment($obx1);
$message->addSegment($obx2);

echo $message->toString(true);

// Parse OBX from existing message
$hl7String = "MSH|^~\\&|Lab|||||||ORU^R01||P|2.3|\r" .
             "OBX|1|NM|2345-7^Glucose^LN||95|mg/dL|70-100|N|||F|||20241215103000\r" .
             "OBX|2|NM|6690-2^WBC^LN||7.5|K/uL|4.5-11.0|N|||F\r" .
             "OBX|3|NM|789-8^RBC^LN||4.8|M/uL|4.2-5.9|N|||F\r";

$message = HL7::from($hl7String)->create();
$obxSegments = $message->getSegmentsByName('OBX');

foreach ($obxSegments as $obx) {
    $identifier = $obx->getObservationIdentifier();
    $value = $obx->getObservationValue();
    $units = $obx->getUnits();
    $status = $obx->getObserveResultStatus();

    echo sprintf("%s: %s %s (%s)\n",
        is_array($identifier) ? $identifier[1] : $identifier,
        $value,
        is_array($units) ? $units[0] : $units,
        $status
    );
}
// Output:
// Glucose: 95 mg/dL (F)
// WBC: 7.5 K/uL (F)
// RBC: 4.8 M/uL (F)

```

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

### AIP::setStartDateTimeOffset

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/AIP.md

Sets the start date and time offset for the segment.

```APIDOC
## AIP::setStartDateTimeOffset

### Description
Sets the start date and time offset.

### Method
`static`

### Endpoint
N/A (Method call)

### Parameters
This function has no parameters.

### Response
#### Success Response (void)
Returns void.

### Request Example
```php
AIP::setStartDateTimeOffset();
```

### Response Example
```
void
```
```

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

### MSH::setReceivingFacility

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/MSH.md

This function has no parameters and returns void.

```php
setReceivingFacility (void)
```

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

### Get ID - IN3::getID

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves the identifier. This function takes no parameters and returns void.

```php
getID (void)
```

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

### ORC::setEnteringDevice API

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/ORC.md

Sets the entering device. This function does not take any parameters and returns void.

```APIDOC
## ORC::setEnteringDevice

### Description
Sets the entering device.

### Method
POST (Assumed, as it's a setter)

### Endpoint
/senaranya/hl7/orc/setEnteringDevice (Assumed)

### Parameters
This function has no parameters.

### Request Body
(No request body is specified for this function)

### Response
#### Success Response (200)
- **return_value** (void) - No value is returned.
```

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

### Segment Field Manipulation

Source: https://github.com/senaranya/hl7/blob/master/docs/Segment.md

Methods for clearing, getting, and setting fields within an HL7 segment.

```APIDOC
## Segment::clearField

### Description
Remove any existing value from the field

### Method
`clearField`

### Parameters
- **index** (int) - Required - Field index

### Return Values
`void`
```

```APIDOC
## Segment::getField

### Description
Get the field at index. If the field is a composite field, it returns an array.

Example:
```php
$field = $seg->getField(9); // Returns a string/null/array depending on what the 9th field is.
```

### Method
`getField`

### Parameters
`This function has no parameters.`

### Return Values
`void`
```

```APIDOC
## Segment::setField

### Description
Set the field specified by index to value. Indices start at 1, to stay with the HL7 standard. Trying to set the value at index 0 has no effect. The value may also be a reference to an array (that may itself contain arrays) to support composite fields (and sub-components).

Examples:
```php
$segment->setField(18, 'abcd'); // Sets 18th field to abcd
$segment->setField(8, 'ab^cd'); // Sets 8th field to ab^cd
$segment->setField(10, ['John', 'Doe']); // Sets 10th field to John^Doe
$segment->setField(12, ['']); // Sets 12th field to ''
```

If values are not provided at all, the method will just return.

### Method
`setField`

### Parameters
- **index** (int) - Required - Index to set

### Return Values
`void`
```

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

### Message::getSegmentByIndex

Source: https://github.com/senaranya/hl7/blob/master/docs/Message.md

Retrieves a segment from the HL7 message by its index. Segment indexing starts at 0.

```APIDOC
## Message::getSegmentByIndex

### Description
Return the segment specified by $index. Note: Segment count within the message starts at 0.

### Method
`public getSegmentByIndex(int $index)`

### Parameters
#### Path Parameters
- **index** (int) - Required - Index where segment is inserted

### Response
#### Success Response (200)
- **void** - Returns the segment at the specified index.
```

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

### EQU Methods

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/EQU.md

Lists the available methods for the EQU segment, including getters, setters, and utility functions.

```APIDOC
### Methods

| Name | Description |
|------|-------------|
|[getAlertLevel](#equgetalertlevel)|
|[getEquipmentInstanceIdentifier](#equgetequipmentinstanceidentifier)|
|[getEquipmentState](#equgetequipmentstate)|
|[getEventDateTime](#equgeteventdatetime)|
|[getLocalRemoteControlState](#equgetlocalremotecontrolstate)|
|[resetIndex](#equresetindex)|Reset index of this segment|
|[setAlertLevel](#equsetalertlevel)|
|[setEquipmentInstanceIdentifier](#equsetequipmentinstanceidentifier)|
|[setEquipmentState](#equsetequipmentstate)|
|[setEventDateTime](#equseteventdatetime)|
|[setLocalRemoteControlState](#equsetlocalremotecontrolstate)|
```

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

### PV1::getServicingFacility

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/PV1.md

Retrieves the servicing facility.

```APIDOC
## PV1::getServicingFacility

### Description
Retrieves the servicing facility.

### Method
GET

### Endpoint
/senaranya/hl7/PV1/getServicingFacility

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **facility** (string) - The servicing facility.

### Response Example
```json
{
  "facility": "General Hospital"
}
```
```

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

### IN3::getPreCertificationRequirement

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves information about pre-certification requirements.

```APIDOC
## IN3::getPreCertificationRequirement

### Description
Retrieves information about pre-certification requirements.

### Method
GET

### Endpoint
/senaranya/hl7/IN3/getPreCertificationRequirement

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **result** (string) - Description of pre-certification requirements.

#### Response Example
```json
{
  "result": "Requires prior authorization for procedures exceeding $5000."
}
```
```

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

### Get Operator - IN3::getOperator

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves operator information. This function takes no parameters and returns void.

```php
getOperator (void)
```

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

### Set Coordination of Benefits Priority - IN1::setCoordOfBenPriority

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN1.md

Sets the coordination of benefits priority. This function takes no parameters and returns void.

```php
setCoordOfBenPriority (void)
```

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

### Get HL7 Segment Name

Source: https://github.com/senaranya/hl7/blob/master/docs/Segment.md

Retrieve the name of the HL7 segment, which is typically the value at index 0.

```php
$name = $seg->getName();
```

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

### ORC::getQuantityTiming

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/ORC.md

Retrieves the quantity and timing information for the order.

```APIDOC
## ORC::getQuantityTiming

### Description
Retrieves the quantity and timing details associated with the order.

### Method
GET

### Endpoint
/senaranya/hl7/orc/quantityTiming

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **quantityTiming** (string) - The quantity and timing information (e.g., '1 tablet daily').

#### Response Example
```json
{
  "quantityTiming": "1 unit every 8 hours"
}
```
```

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

### Get Verification Status - IN1::getVerificationStatus

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN1.md

Retrieves the verification status. This function takes no parameters and returns void.

```php
getVerificationStatus (void)
```

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

### SAC::getSpecimenComponent

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/SAC.md

Retrieves the specimen component. This function takes no parameters and returns void.

```php
getSpecimenComponent (void)
```

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

### Get Certified By - IN3::getCertifiedBy

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves information about who certified the entity. This function takes no parameters and returns void.

```php
getCertifiedBy (void)
```

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

### SAC::getSpecimenSource

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/SAC.md

Retrieves the specimen source. This function takes no parameters and returns void.

```php
getSpecimenSource (void)
```

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

### Get Certification Required - IN3::getCertificationRequired

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Checks if certification is required. This function takes no parameters and returns void.

```php
getCertificationRequired (void)
```

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

### SAC::getInitialSpecimenVolume

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/SAC.md

Retrieves the initial volume of the specimen.

```APIDOC
## SAC::getInitialSpecimenVolume

### Description
Retrieves the initial volume of the specimen.

### Method
GET

### Endpoint
/senaranya/hl7/SAC/getInitialSpecimenVolume

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **result** (string) - The initial volume of the specimen.

#### Response Example
```json
{
  "result": "volume"
}
```
```

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

### Get Certification Number - IN3::getCertificationNumber

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves the certification number. This function takes no parameters and returns void.

```php
getCertificationNumber (void)
```

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

### ORC::getEnteringDevice

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/ORC.md

Retrieves information about the device used for entering the order.

```APIDOC
## ORC::getEnteringDevice

### Description
Retrieves information about the device used to enter the order.

### Method
GET

### Endpoint
/senaranya/hl7/orc/enteringDevice

### Parameters
This function has no parameters.

### Response
#### Success Response (200)
- **enteringDevice** (object) - Information about the entering device.
  - **type** (string) - Type of device (e.g., 'Workstation', 'Tablet').
  - **identifier** (string) - Unique identifier for the device.

#### Response Example
```json
{
  "enteringDevice": {
    "type": "Workstation",
    "identifier": "WS-LAB-05"
  }
}
```
```

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

### Get HL7 Segment Size

Source: https://github.com/senaranya/hl7/blob/master/docs/Segment.md

Determine the number of fields present in the HL7 segment, excluding the segment name itself.

```php
$size = $seg->size();
```

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

### MSH::setSecurity

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/MSH.md

This function has no parameters and returns void.

```php
setSecurity (void)
```

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

### Get Verification Date/Time - IN1::getVerificationDateTime

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN1.md

Retrieves the verification date and time. This function takes no parameters and returns void.

```php
getVerificationDateTime (void)
```

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

### Segment Constructor

Source: https://github.com/senaranya/hl7/blob/master/docs/Segment.md

Initializes a new HL7 segment with a name and optional fields.

```APIDOC
## Segment::__construct

### Description
Create a segment.

A segment may be created with just a name or a name and an array of field values. The segment name should be a standard HL7 segment (e.g. MSH / PID etc.) that is three characters long, and upper case. If an array is given, all fields will be filled from that array. Note that for composed fields and sub-components, the array may hold sub-arrays and sub-sub-arrays. Repeated fields can not be supported the same way, since we can't distinguish between composed fields and repeated fields.

Example:
```php
$seg = new Segment("PID");

$seg->setField(3, "12345678");
echo $seg->getField(1);
```

### Method
`__construct`

### Parameters
- **name** (string) - Required - Name of the segment
- **fields** (array|null) - Optional - Fields for segment

### Return Values
`void`

### Throws Exceptions
- `\InvalidArgumentException`
```

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

### EQU::getEquipmentInstanceIdentifier

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/EQU.md

Retrieves the equipment instance identifier.

```APIDOC
### EQU::getEquipmentInstanceIdentifier

**Description**
```php
 getEquipmentInstanceIdentifier (void)
```

**Parameters**
`This function has no parameters.`

**Return Values**
`void`
```

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

### Segment - Field Operations

Source: https://context7.com/senaranya/hl7/llms.txt

Provides methods to get and set fields within a segment, supporting composite fields and sub-components.

```APIDOC
## Segment - Field Operations

### Description
Provides methods to get and set fields within a segment, supporting composite fields and sub-components.

### Method
N/A (Class methods)

### Endpoint
N/A

### Parameters
N/A

### Request Example
```php
<?php
use Aranyasen\HL7;
use Aranyasen\HL7\Segment;

// Create a generic segment
$segment = new Segment('OBR');

// Set simple field values
$segment->setField(1, 1);                    // Set ID
$segment->setField(2, 'ORDER001');           // Placer Order Number
$segment->setField(4, 'CBC^Complete Blood Count^L');  // Universal Service ID

// Set composite fields using arrays
$segment->setField(16, ['Smith', 'John', 'MD']);  // Ordering Provider: Smith^John^MD

// Set nested sub-components
$segment->setField(32, [
    ['Principal', 'PI'],   // First component with sub-components
    'Secondary'            // Second component
]);

// Clear a field value
$segment->clearField(3);

// Get field values
$orderId = $segment->getField(2);            // Returns: 'ORDER001'
$provider = $segment->getField(16);          // Returns: ['Smith', 'John', 'MD']
$missingField = $segment->getField(99);      // Returns: null

// Get multiple fields at once
$fields = $segment->getFields(1, 5);         // Get fields 1-5
$allFields = $segment->getFields();          // Get all fields

// Get segment info
$name = $segment->getName();                 // Returns: 'OBR'
$fieldCount = $segment->size();              // Returns number of fields

// Working with parsed segments
$hl7String = "MSH|^~\\&|||||||ORU^R01||P|2.3|\nOBR|1|ORD123||80053^Comprehensive Metabolic Panel^L|||20241215|";
$message = HL7::from($hl7String)->create();

$obr = $message->getFirstSegmentInstance('OBR');
$serviceId = $obr->getField(4);  // Returns: ['80053', 'Comprehensive Metabolic Panel', 'L']
?>
```

### Response
N/A
```

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

### Get Physician Reviewer - IN3::getPhysicianReviewer

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves information about the physician reviewer. This function takes no parameters and returns void.

```php
getPhysicianReviewer (void)
```

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

### Get Second Opinion Status - IN3::getSecondOpinionStatus

Source: https://github.com/senaranya/hl7/blob/master/docs/Segments/IN3.md

Retrieves the status of the second opinion. This function takes no parameters and returns void.

```php
getSecondOpinionStatus (void)
```