PBC Library Manual 0.5.11 - Stanford Crypto Group

4.1. Initializing elements
Chapter 4. Element functions
When an element is initialized it is associated with an algebraic structure, such as a particular finite field
or elliptic curve group.
We use G1 and G2 to denote the input groups to the pairing, and GT for the output group. All have order
r, and Zr means the ring of integers modulo r. G1 is the smaller group (the group of points over the base
field). With symmetric pairings, G1 = G2.
void element_init_G1(element_t e, pairing_t pairing)
void element_init_G2(element_t e, pairing_t pairing)
void element_init_GT(element_t e, pairing_t pairing)
Initialize e to be an element of the group G1, G2 or GT of pairing.
void element_init_Zr(element_t e, pairing_t pairing)
Initialize e to be an element of the ring Z_r of pairing. r is the order of the groups G1, G2 and GT that are
involved in the pairing.
void element_init_same_as(element_t e, element_t e2)
Initialize e to be an element of the algebraic structure that e2 lies in.
void element_clear(element_t e)
Free the space occupied by e. Call this when the variable e is no longer needed.
4.2. Assigning elements
These functions assign values to elements. When integers are assigned, they are mapped to algebraic
structures canonically if it makes sense (e.g. rings and fields).
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