import { DType, Tensor } from '../../../library';
import { BackwardOp, VariableI } from '../../types';
export declare class SigmoidBack<DTpe extends DType> implements BackwardOp<DTpe> {
    input: VariableI<DTpe>;
    sigmoid: Tensor<DTpe>;
    constructor(input: VariableI<DTpe>, sigmoid: Tensor<DTpe>);
    backward(grad: Tensor<DTpe>): void;
    delete(): void;
}