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Advanced Search on ContraDB

Introduction

You can search dances for patterns of figures. This somewhat dated video walks you through it.

Filter Operator Reference

figure

The dance matches if and only if (iff) there is a figure somewhere in the dance.

formation

The dance matches iff it's formation matches.

and

Matches iff all the subexpressions match the dance.

or

Matches iff any of the subexpressions match the dance.

no

Matches iff the subexpression does not match the dance.

then

Like and, but the subexpressions have to match in the order they appear in the dance, directly abuting each other. For example, You can use this to check for dances with a roll away immediately followed by a swing, whereas with and you could only check to see if the dance had both a roll away and a swing.

Note: this search wraps around the end of the dance, so allemande then allemande will match a dance where the first and last figures are allemandes.

then gets more interesting when it's subexpressions are more than simple figures - e.g. not and all, but for that we need a more complicated understanding of queries.

Queries Actually Match Choreography within a Dance - 'Patches'

Up until now, it's been possible to think of each query matching or not matching on a dance as a whole. But in order to do more complicated queries, we'll need to think of a query matching or not matching on the dance as a whole and also on sets of consecutive figures (here called 'patches', but not called that in the source code).

If a query doesn't match a dance, then it can have no matching patches. A query can match a dance, and match zero or more patches - we'll see an example of a dance matching with zero figures with and, below.

figure

Patches 1 figure long, equal to that figure, match.

or

The dance matches if any subexpression matches. The matched patches are the unions of the subexpressions' matched patches.

and

The dance matches if all the subexpressions match. Individual patches match if they're matched by each subexpression.

It's common to have a matching dance that has zero matching subexpressions. E.g. chain and hey will match lots of dances, but since no single figure is both a chain and a hey, no figures will ever match.

&

Like and, but the dance will only match if there is at least one matching patch.

no

The dance matches iff the subexpression doesn't match. If the dance matches, then all 1-fiugre-long patches match.

This is important if you're using then: swing then no hey will match the same dances as swing and no hey - likely not what you intended.

not ('figurewise not')

What we were maybe trying to get in the previous example was a search for dances that had a swing followed by any move besides a hey, but that were still allowed to have heys elsewhere in the dance. Enter not. not matches all figures (length-1 patches)+ that are not matched by their subexpression. swing then not hey - will match dances with a swing followed by any figure not a hey.

not was formerly called 'anything but'.

all

The dance matches only if every figure matches - this isn't too practical, and anyway all figure x is equivalent to not no figure x, but it seems somehow to complete the set. Here's one possible application: imagine teaching contra to a preschool, and you want to find only dances with certain figures. You could use: all (swing or allemande or circle or do si do or star or ...) to search for dances that use only simple moves.