braintools.cogtask.cos_sin#
- braintools.cogtask.cos_sin(key, num_dirs, repeats=1, *, base_value=0.0, map_to_01=True)[source]#
Encode a discrete direction index into repeated [cos(theta), sin(theta)] features.
- Output dim: 2 * repeats
[cos(theta)] repeated ‘repeats’ times, then [sin(theta)] repeated ‘repeats’ times.
- Parameters:
key (
str) – Context key containing discrete direction index (int).num_dirs (
int) – Number of discrete directions (e.g., num_stimuli).repeats (
int) – How many duplicated cos features and sin features.base_value (
float) – Baseline after mapping to [0,1]. Ignored if map_to_01=False.map_to_01 (
bool) – If True, map cos/sin from [-1,1] to [0,1], then to [base_value, 1]. If False, keep raw cos/sin in [-1,1].
- Return type:
Notes
This encoder ignores feature.num (it will validate it equals 2*repeats).