What ⤅ means
Read from the value on the left to its result. A mapping is a rule that associates an input with an output. The starting bar marks the input side; both arrowheads point toward the output. “Two-headed” describes two tips pointing the same way, not an arrow going in both directions.
The familiar shows how an individual input is mapped. ⤅ gives mathematical writers a separate, two-headed form, so retain the extra tip when reproducing a formula. This belongs to a wider repertoire of arrows encoded for mathematical typesetting, drawing on standardized mathematical symbol lists and scientific publishing needs.
Part of collections
Related characters
2
Questions people ask
1Does ⤅ always mean a function is onto?
No. “Onto,” or surjective, means every element of the target set is reached. Two-headed arrows can signal this property, but ⤅ alone does not guarantee it; check the writer’s definition.
More like this
9
How to type or find ⤅
- Search it as
- two-headed maps-to arrow · twoheaded mapsto · math arrow · ⤅ meaning · double headed right arrow · two headed right arrow · double arrow with bar · surjective map arrow · surjection arrow
- Shows up in
- Anything that takes text · its shape is whatever your font draws
⤅\2905Why is ⤅ a box on my screen?
fsymbols draws rare signs with its own fonts, so they show here even where your device has none. An app or website without such a font shows an empty box (□) or a question mark instead. Turn our fonts off to see each sign as your device draws it by itself: a box here means a box in your chats and documents too.
Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.