# score.freq

### analyze-intervals

`(analyze-intervals chord)`
```Creates an interval list from a pch chord
```

### cents->scaler

`(cents->scaler cents)`
```Converts the cents into a scaler value 2^(cents/1200).

Translated from Common Music.```

### hertz

`(hertz a)`
```General function for converting value a to frequency.  It will convert
keywords, MIDI note numbers, PCH, strings, and symbols.```

### invert

`(invert [base-pch & more :as pchs] inversion)`
```Inverts a list of pchs given the version number
```

### keynum

`(keynum a)`
```General function for converting value a to MIDI notenumber.  It will convert
keywords, PCH, strings, and symbols, and return any other value. Assumes PCH
is 12 TET with [8 0] as Middle-C (MIDI Note 60).```

### keyword->freq

`(keyword->freq sym)`
```Convert keyword or symbol to frequency (i.e. :A4 is 440.0)
```

### keyword->notenum

`(keyword->notenum sym)`
```Converts keyword or symbol to MIDI notenum (i.e. :C4 is 60, :Cs4 is 61)
```

### midi->freq

`(midi->freq notenum)`
```Convert MIDI Note number to frequency in hertz
```

### pch->freq

`(pch->freq pch)`
```Converts PCH to frequency. [8 0] is equivalent to Middle-C (MIDI Note 60),
which is equivalent to :C4.  Assumes 12 scale degrees per octave (12 TET).```

### pch->notenum

`(pch->notenum pch)``(pch->notenum [oct scale-degree] scale-degrees)`
```Converts PCH notation to note number. Optional number of
scale degrees per octave, defaults to 12.```

### pch->sco

`(pch->sco [a b])`
```Converts PCH notation to Csound-style pch string.
```

`(pch-add pch interval)``(pch-add pch interval scale-degrees)`
```Add interval to pch (i.e. [8 0] 11 => [8 11]). Defaults to 12-tone octave.
```

### pch-diff

`(pch-diff pch1 pch2)``(pch-diff pch1 pch2 scale-degrees)`
```Return the interval between two pitches (i.e. [8 0] [9 1] => 13). Defaults
to 12-tone octave.```

### pch-interval-sco

`(pch-interval-sco pch intervals)``(pch-interval-sco pch intervals scale-degrees)`
```Given a base PCH pch and sequence of intervals x, generates a sequence of Csound pch strings.  For
example, (pch-interval-seq [8 0] [1 -2]) will yield ("8.0" "8.01" "7.11").```

### pch-interval-seq

`(pch-interval-seq pch x)``(pch-interval-seq pch x scale-degrees)`
```Given a base PCH pch and sequence of intervals x, generates a sequence of PCH's.  For
example, (pch-interval-seq [8 0] [1 -2]) will yield ([8 0] [8 1] [7 11]).```

### scaler->cents

`(scaler->cents scalar)`
```Converts a scaler into a cents value 1200*log2(ratio).

Translated from Common Music.```

### str->freq

`(str->freq sym)`
```Convert string to frequency (i.e. "A4" is 440.0)
```

### str->notenum

`(str->notenum sym)`
```Converts string to MIDI notenum (i.e. "C4" is 60, "Cs4" is 61)
```

### sym->freq

`(sym->freq sym)`
```Convert keyword or symbol to frequency (i.e. :A4 is 440.0)
```

### sym->notenum

`(sym->notenum sym)`
```Converts keyword or symbol to MIDI notenum (i.e. :C4 is 60, :C#4 is 61).
```