subtract

Engine.subtract(x, y)

Returns a ciphertext that represents the result of subtracting two inputs.

• Input:
  • x: int, double, complex double, array_like, Plaintext, or Ciphertext
  • y: int, double, complex double, array_like, Plaintext, or Ciphertext
  • If either input is a scalar, the scalar is subtracted from every value of the other input.
  • At least one of the inputs must be a ciphertext.
• Output:
  • ciphertext

Examples

Subtraction between two ciphertexts

from desilofhe import Engine

engine = Engine()
secret_key = engine.create_secret_key()
public_key = engine.create_public_key(secret_key)

message1 = [1, 2, 3]
ciphertext1 = engine.encrypt(message1, public_key)

message2 = [4, 5, 6]
ciphertext2 = engine.encrypt(message2, public_key)

subtracted = engine.subtract(ciphertext1, ciphertext2)

Subtraction of a message from a ciphertext

from desilofhe import Engine

engine = Engine()
secret_key = engine.create_secret_key()
public_key = engine.create_public_key(secret_key)

message1 = [1, 2, 3]
ciphertext1 = engine.encrypt(message1, public_key)

message2 = [4, 5, 6]
ciphertext2 = engine.encrypt(message2, public_key)

subtracted1 = engine.subtract(ciphertext1, message2)
subtracted2 = engine.subtract(message1, ciphertext2)

Subtraction of a scalar from a ciphertext

from desilofhe import Engine

engine = Engine()
secret_key = engine.create_secret_key()
public_key = engine.create_public_key(secret_key)

message = [1, 2, 3]
ciphertext = engine.encrypt(message, public_key)

subtracted1 = engine.subtract(ciphertext, 2)
subtracted2 = engine.subtract(2, ciphertext)

Subtraction of a plaintext from a ciphertext

from desilofhe import Engine

engine = Engine()
secret_key = engine.create_secret_key()
public_key = engine.create_public_key(secret_key)

message1 = [1, 2, 3]
plaintext1 = engine.encode(message1)
ciphertext1 = engine.encrypt(plaintext1, public_key)

message2 = [4, 5, 6]
plaintext2 = engine.encode(message2)
ciphertext2 = engine.encrypt(plaintext2, public_key)

subtracted1 = engine.subtract(ciphertext1, plaintext2)
subtracted2 = engine.subtract(plaintext1, ciphertext2)