o ?߱i$@sBddlmZmZddlZddlmZdejdejfddZdejdejfdd Zd ejdejd ejd ejd ejdejdejfddZ d ejd ejdejd ejdeejejff ddZ d ejd ejdejdejdeejejff ddZ d ejd ejdejdedeejejff ddZ d ejd ejdejdedeejejff ddZ d ejd ejdejdedeejejff ddZd ejd ejdejdedeejejff ddZd ejd ejdejdedeejejff dd Zd ejd ejdejdedeejejff d!d"Ze ee eeed#Zd$edefd%d&Zd$edefd'd(ZdS)))CallableTupleN batch_multreturncCs*|j}|jtjd}t||j|dS)z Compute the first order phi function: (exp(t) - 1) / t. Args: t: Input tensor. Returns: Tensor: Result of phi1 function. dtype)r totorchfloat64expm1r input_dtyper`/data/cameron/vidgen/cosmos-predict2.5/cosmos_predict2/_src/imaginaire/functional/runge_kutta.pyphi1s rcCs,|j}|jtjd}t|d|j|dS)z Compute the second order phi function: (phi1(t) - 1) / t. Args: t: Input tensor. Returns: Tensor: Result of phi2 function. r?)r r r r rrrrrphi2&s rx_ssx0_ss1x0_s1c Cst| }t| }t| }||}ttj|t|ddr(Jdttj||t|ddr)atolzStep size is too smallrg)nan) r loganyisclose zeros_likerr nan_to_numrexp) rrrrrrmdtc2Zphi1_valZphi2_valb1b2rrrres_x0_rk2_step5s   $( ,r'cCs,|||}||}t||t|||fS)a3 Perform a regularized Euler step based on x0 prediction. Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. x0_s: Prediction at current time. Returns: Tuple[Tensor, Tensor]: Updated state tensor and current prediction. r)rrrrZcoef_x0Zcoef_xsrrrreg_x0_euler_step`s r(eps_scCs$|t||||t|d|fS)aD Perform a regularized Euler step based on epsilon prediction. Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. eps_s: Epsilon prediction at current time. Returns: Tuple[Tensor, Tensor]: Updated state tensor and current x0 prediction. rr)rrrr)rrrreg_eps_euler_stepws$r*x0_fncCs|||}t||||S)a Perform a first-order Runge-Kutta (Euler) step. Recommended for diffusion models with guidance or model undertrained Usually more stable at the cost of a bit slower convergence. Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. x0_fn: Function to compute x0 prediction. Returns: Tuple[Tensor, Tensor]: Updated state tensor and x0 prediction. )r()rrrr+rrrr rk1_eulers r,cCs8t||}t||||\}}|||}t||||S)a8 Perform a stable second-order Runge-Kutta (midpoint) step. Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. x0_fn: Function to compute x0 prediction. Returns: Tuple[Tensor, Tensor]: Updated state tensor and x0 prediction. )r sqrtr,r()rrrr+rx_s1_rrrrrk2_mid_stables r0cCs@t||}t||||\}}|||}t|||||||fS)a1 Perform a second-order Runge-Kutta (midpoint) step. Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. x0_fn: Function to compute x0 prediction. Returns: Tuple[Tensor, Tensor]: Updated state tensor and x0 prediction. )r r-r,r')rrrr+rr.rrrrrrk2_mids  r1c CsZt||||\}}td|||}|||}td|||}||d} t|||| S)a Perform a naive second-order Runge-Kutta (Heun's method) step. Impl based on rho-rk-deis solvers, https://github.com/qsh-zh/deis Recommended for diffusion models without guidance and relative large NFE Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. x0_fn: Function to compute x0 prediction. Returns: Tuple[Tensor, Tensor]: Updated state tensor and current state. rr,rr*) rrrr+x_trr)x0_tZeps_tavg_epsrrrrk_2heun_naives   r7cCs6t||||\}}|||}||d}t||||S)ak Perform a naive second-order Runge-Kutta (Heun's method) step. Impl based no EDM second order Heun method Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. x0_fn: Function to compute x0 prediction. Returns: Tuple[Tensor, Tensor]: Updated state tensor and current state. r2)r,r()rrrr+r4rr5Zavg_x0rrr rk_2heun_edms  r8cCsd\}}d\}}d\}} } ||} || |} || |} t||| |\}}td|||}||| }td| ||}||||}t||| |\}}||| }td| ||}||| || |}t||||S)a Perform a naive third-order Runge-Kutta step. Impl based on rho-rk-deis solvers, https://github.com/qsh-zh/deis Recommended for diffusion models without guidance and relative large NFE Args: x_s: Current state tensor. s: Current time tensor. t: Target time tensor. x0_fn: Function to compute x0 prediction. Returns: Tuple[Tensor, Tensor]: Updated state tensor and current state. )g?r)gg@)UUUUUU?gUUUUUU?r9rr3)rrrr+r$c3Za31Za32r%r&b3deltars2r.rr)rZeps_s1_epsZx_s2r/Zx0_s2Zeps_s2r6rrrrk_3kutta_naives      r?)1euler2midZ 2mid_stableZ 2heun_edmZ 2heun_naiveZ 3kutta_naivenamecCs,|tvrt|Sdt}td|)z Get the specified Runge-Kutta function. Args: name: Name of the Runge-Kutta method. Returns: Callable: The specified Runge-Kutta function. Raises: RuntimeError: If the specified method is not supported. z z1Only support the following Runge-Kutta methods: )RK_FNsjoinkeys RuntimeError)rBmethodsrrrget_runge_kutta_fn0s rHcCs|tvS)z Check if the specified Runge-Kutta function is supported. Args: name: Name of the Runge-Kutta method. Returns: bool: True if the method is supported, False otherwise. )rC)rBrrris_runge_kutta_fn_supportedCs rI)typingrrr Z4cosmos_predict2._src.imaginaire.functional.batch_opsrTensorrrr'r(r*r,r0r1r7r8r?rCstrrHboolrIrrrrs  +    0   *