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Laboratory of Neuropsychology

MatOff Data File Structure

MatOFF Data file structure

Index File (.index)

Size
(decimal bytes)

Cumulative (hex bytes)

Data Type / Name Information Stored Measure

4

0-3

int trial trial number

4

1C-1F

unsigned long event starting file position in bytes

4

20-23

unsigned long event length in 8-byte records

4

24-27

unsigned long pulse starting file position in bytes

4

28-2B

unsigned long pulse length in 8-byte records

4

2C-2F

unsigned long analog starting file position in bytes

4

30-33

unsigned long analog length in 4-byte records

28 (dec)

1C (hex)

Total bytes

record length

Final entry in Index File has trial=-1 and all other values=0.
Limits imposed by file structure:

Maximum number of trials (absolute trial number in entire file) 2,147,483,647
Maximum file size (last record that can be addressed) 2,147,483,647

Unit Definition File (.udef)

Size
(decimal bytes)

Cumulative (hex bytes)

Data Type /

Name

Information Stored Measure

12

0-B

char unit name in bytes
unsigned short pulse channel in bytes

87

D-63

char trials for this unit in bytes

100 (dec)

63 (hex)

Total bytes

record length

Final entry in UDF File has unit name=’END_OF_FILE’, trial=255, trial list string=’0-0’.
List of trials is ASCII string. Example: ‘22-55,56-60,60-120,135-240’.
Limits imposed by file structure:

Longest unit name 12 characters
Highest pulse channel number 254
Longest list of trials in unit 87 bytes

Event Data File (.event)

bytes

0-3

4-7

Total record length

Entry type

Data type (4 bytes)

Event time (4 bytes)

8 bytes

trial header

-1 (header marker)

trial number

starts at trial #1

Data

event code

event time

time units of .0001 sec

Limits imposed by file structure:

Highest event code number 2,147,483,647
Longest trial (time) 214,748.3647 sec ~ 59.65 hours
Maximum number of trials (absolute trial number in entire file) 2,147,483,647

Pulse Data File (.pulse)

bytes

0-3

4-7

Total record length

Entry size

4 byte

4 bytes

8 bytes

trial header

-1 (header marker)

trial number

starts at trial #1

data

pulse channel

pulse time

time units of .0001 sec

Limits imposed by file structure:

Number of different spike (pulse) channels 2,147,483,647
Longest trial (time) 214,748.3647 s ~ 59.65 hours
Maximum number of trials (absolute trial number in entire file) 2,147,483,647

Analog Data File (.analog)

bytes

0-1

2-3

Total record length

Entry size

2 byte

2 bytes

4 bytes

trial header

-1 (header marker)

trial number,
modulo 32768

data

channel

data value

Limits imposed by file structure:

Number of different analog channels 32,768
Analog value range -32,768 to 32,767
Number of trials (absolute trial number in entire file) 2,147,483,647

History Index File (.hindex)

Size
(decimal bytes)

Cumulative (hex bytes)

Data Type / Name Information Stored Measure

12

0-B

char array unit name chars

4

C-F

unsigned long history starting file position in bytes

4

10-14

unsigned long history length in bytes

20 (dec)

14 (hex)

Total bytes

record length

Final entry in History Index File has:
Unit Name = ‘END_OF_FILE’ Starting file position = 0 Length = 0
Limits imposed by file structure:

Maximum number of trials 2,147,483,647
Maximum file size (last record that can be addressed) 2,147,483,647

History Data File (.history)

Entry type Data type Data size
HEADER
unit header -1 (int16) 2 bytes
unit name char array 12 bytes
DATA repeated for each class
class int16 2 bytes
number of trials int16 2 bytes
list size int16 2 bytes
class trial list char array list size * char
class values int16 number of trials * 2 bytes

Final entry in History File has:
Header = -1 Unit Name = ‘END_OF_FILE’ Class = 0 number_of_trials = 0 list size = 0
no class trial list or class values.