# Representation: **metpos¶

## Humdrum Representation for Metric Hierarchy¶

### REPRESENTATION¶

**metpos – position in metric hierarchy

### DESCRIPTION¶

The **metpos representation consists of simply a set of numerical values indicating the order of events. Normally, a **metpos spine simply encodes a set of ascending integers marking the succession of events:

 **metpos 1 2 3 4 5 *-

The **metpos representation also recognizes **kern-like **barlines**. The presence of an equals-sign  (=) in the first column of a **metpos spine is used to denote a barline. Immediately after the equals sign there may follow an optional integer value indicating the measure number (e.g.  =107 – for measure 107). In addition, a lower-case alphabetic character may be appended to the measure number – as in:  =14b. This convention permits the user to distinguish measure numbers for first and second endings. Measure numbers refer to the information immediately following the barline, thus the token  =23 occurs just prior to the encoded beats for measure 23.

Double barlines are indicated by using two or more successive equals signs  (==). Several consecutive equals signs may be encoded in order to enhance readability (e.g.  =======). An additional attribute for barlines is the pause – which is represented by the– icolon (;). Thus the token  =4; means that the barline starting measure number 4 has a pause written above or below it, while the token  =====; means that a double barline contains a pause indication.

### FILE TYPE¶

It is recommended that files containing predominantly **metpos data should be given names with the distinguishing .mtp’ extension.

### SIGNIFIERS¶

The following table summarizes the **metpos mappings of signifiers and signifieds.

 0-9 decimal values . fractional delimiter; null token = barlines == double barline

Summary of ***metpos** Signifiers*

### EXAMPLES¶

A sample document is given below:

 **kern **metpos *M4/4 *M4/4 *tb16 *tb16 *c: * =1 =1 8r 1 . 5 16cc 4 16bn 5 8cc 3 . 5 8g 4 . 5 8a- 2 . 5 16cc 4 16b 5 8cc 3 . 5 8dd 4 . 5 =2 =2 *- *-

### PERTINENT COMMANDS¶

The following Humdrum commands accept **metpos encoded data as inputs:

 **synco** measure degree of metric syncopation **urrhythm** characterize the rhythmic prototypes in a passage

The following Humdrum command produces **metpos data as output:

 **metpos** generate metric position values for timebase-formatted **kern or **recip inputs

### TANDEM INTERPRETATIONS¶

The following tandem interpretations can be used in conjunction with **metpos:

 MIDI channel *Ch1 meter signatures *M6/8 tempo *MM96.3 timebase *tb32

Tandem interpretations for ***metpos***

 barlines, **date, **dur, **kern, kern, metpos, **ordo, **recip, **takt, **time, timebase, **Zeit`