Points.count¶

Points.count(condition, features=None)¶

The number of points which satisfy the condition.

Parameters:

condition (function, query) –
- function - accepts a point as its only argument and returns a boolean value to indicate if the point should be counted
- query - string in the format ‘FEATURENAME OPERATOR VALUE’ (i.e “ft1 < 10”, “id4 == yes”, or “col4 is nonZero”) where OPERATOR is separated from the FEATURENAME and VALUE by whitespace characters. See nimble.match.QueryString for string requirements.
features (None, identifier, list of identifiers) – Only apply the condition function to a selection of features in each point. May be a single feature name or index, an iterable, container of feature names and/or indices. None indicates application to all features.

Returns:

int

Examples

Count using a python function.

>>> def sumIsOne(pt):
...     return sum(pt) == 1
>>> X = nimble.identity(3)
>>> X.points.count(sumIsOne)
3

Count when the query string returns True.

>>> X = nimble.identity(3, featureNames=['ft1', 'ft2', 'ft3'])
>>> X.points.count("ft1 == 0")
2

Keywords: number, counts, tally

Nimble