# Difference between revisions of "Humdrum homework"

## Music 253 Humdrum Homework

Examine melodic and harmonic properties of the Bach chorale data set. Refer to Humdrum Lab 1 for how to download the chorales (and install the tools useful for the homework).

### Melodic intervals

Here is a template for extracting the melodic intervals for the tenor part in the chorales and plotting them in a histogram by percentages:

```    extractx -s 2 *.krn | mint | ridx -H | grep -v [r[] | \
sortcount -vp --sort interval -T "Tenor melodic intervals" > melodic-tenor.html
```

The following plot should be displayed when opening up the generated HTML file:

[Move your mouse over the histogram bars to view the numeric values for the percentages.]

Also make plots for bass (spine 1), alto (spine 3), and soprano (spine 4) and visually compare the plots to each other.

#### Questions

1. Which part has the most repetitions (P1 interval)? And which has the least repetitions?

2. Which part has the most leaps (intervals greater than 2 or less than -2)?

3. Which stepwise direction is more common in each voice, going up a step or down a step? A "step" should be considered the sum of the "m2" and "M2" categories.

4. Is it more common to leap up or down in each voice (sum all of the [most common] intervals above +2/below -2)?

### Harmonic intervals

Here is an example of how to extract the harmonic intervals between the soprano and bass parts:

```    extractx -s 1,4 *.krn | hint | ridx -H | grep -v [r-] | sortcount -pv -T "Harmonic intervals between Soprano and Bass" --sort interval  > analysis.html
```

This plot should be displayed when opening up the generated HTML file:

Make plots comparing each pair of parts bass (spine 1), tenor (spine 2), alto (spine 3), and soprano (spine 4), which is a total of 6 plots.

#### Questions

5. What is the most common harmonic interval between each part pair?