MATLAB Crash Log Analysis Techniques: Extracting Fault Information from Logs for Rapid Issue Localization

# 1. Overview of MATLAB Crashes**

A MATLAB crash refers to the sudden shutdown of the MATLAB application during operation, usually accompanied by an error message or no prompt at all. Crash issues can significantly affect user experience and work efficiency, making it crucial to locate and resolve them in a timely manner. This chapter will introduce common causes and symptoms of MATLAB crashes, laying the foundation for subsequent log analysis and troubleshooting.

# 2. Log File Analysis

### 2.1 Structure and Format of Log Files

MATLAB log files usually adopt a text format, with their structure and format as follows:

| Field | Description |
|---|---|
| Timestamp | The time the log message was recorded |
| Log Level | The severity level of the log message, such as INFO, WARNING, ERROR |
| Component | The MATLAB component that generated the log message |
| Message | Detailed content of the log message |

### 2.2 Common Types of Log Files

MATLAB generates various types of log files, some of the common ones include:

| Log File Type | Purpose |
|---|---|
| MATLAB.log | Records all log messages during a MATLAB session |
| <component>.log | Records log messages for a specific MATLAB component, such as simulink.log |
| <function>.log | Records log messages for a specific MATLAB function, such as optimset.log |

### 2.3 Log File Analysis Tools

MATLAB offers several tools for analyzing log files:

| Tool | Purpose |
|---|---|
| `diary` | Saves log messages from a MATLAB session to a file |
| `logread` | Reads and parses log files |
| `logquery` | Queries and filters log files |

**Code Block 1: Using `logread` to read log files**

% Read the MATLAB.log file
logData = logread('MATLAB.log');

% Extract timestamps
timestamps = logData.time;

% Extract log levels
logLevels = logData.level;

% Extract components
components = ***ponent;

% Extract messages
messages = logData.message;

**Logical Analysis:**

The `logread` function reads the log file and parses it into a structure `logData`. This structure contains fields `time`, `level`, `component`, and `message`, which represent the timestamp, severity level, component, and message content of the log messages, respectively.

**Parameter Description:**

* `filename`: The path to the log file to be read.

**Code Block 2: Using `logquery` to filter log files**

% Query log messages with the INFO level
infoMessages = logquery('MATLAB.log', 'level', 'INFO');

% Query log messages from the simulink component
simulinkMessages = logquery('MATLAB.log', 'component', 'simulink');

% Query log messages containing a specific keyword
keywordMessages = logquery('MATLAB.log', 'message', 'Error');

**Logical Analysis:**

The `logquery` function filters log files based on specified conditions. It returns a structure containing the log messages that meet the conditions.

**Parameter Description:**

* `filename`: The path to the log file to be queried.
* `filter`: The condition used to filter log messages. Conditions can be `level`, `component`, `message`, or a combination of them.
* `value`: The value of the condition.

# 3. Fault Information Extraction

### 3.1 Identification of Crash-Related Error Messages

MATLAB crashes are usually accompanied by error messages, ***mon crash-related error messages include:

- **MATLAB: Runtime error:** This is the most common