updated readme

README.md

@@ -327,25 +327,26 @@ There is a lot more you can do to interface with CyRK's C++ backend and fully op
 
 ```cython
 cdef shared_ptr[CySolverResult] cysolve_ivp(
-    DiffeqFuncType diffeq_ptr,    # Differential equation defined as a cython function
-    double* t_span_ptr,           # Pointer to array (size 2) of floats defining the start and stop points for integration
-    double* y0_ptr,               # Pointer to array defining initial y0 conditions.
-    unsigned int num_y,           # Size of y0_ptr array.
-    unsigned int method = 1,      # Integration method. Current options: 0 == RK23, 1 == RK45, 2 == DOP853
-    double rtol = 1.0e-3,         # Relative tolerance used to control integration error.
-    double atol = 1.0e-6,         # Absolute tolerance (near 0) used to control integration error.
-    double* args_ptr = NULL,      # Pointer to array of additional arguments passed to the diffeq. Currently cysolve_ivp only supports doubles as additional arguments.
-    unsigned int num_extra = 0,   # Number of extra outputs you want to capture during integration. There is a performance hit if this is used in conjunction with t_eval or dense_output.
-    size_t max_num_steps = 0,     # Maximum number of steps allowed. If exceeded then integration will fail. 0 (the default) turns this off.
-    size_t max_ram_MB = 2000,     # Maximum amount of system memory the integrator is allowed to use. If this is exceeded then integration will fail.
-    bint dense_output = False,    # If True, then dense interpolators will be saved to the solution. This allows a user to call solution as if a function (in time).
-    double* t_eval = NULL,        # Pointer to an array of time steps at which to save data. If not provided then all adaptive time steps will be saved. There is a slight performance hit using this feature.
-    size_t len_t_eval = 0,        # Size of t_eval.
-    double* rtols_ptr = NULL,     # Overrides rtol if provided. Pointer to array of floats of rtols if you'd like a different rtol for each y.
-    double* atols_ptr = NULL,     # Overrides atol if provided. Pointer to array of floats of atols if you'd like a different atol for each y.
-    double max_step = MAX_STEP,   # Maximum allowed step size.
-    double first_step = 0.0       # Initial step size. If set to 0.0 then CyRK will guess a good step size.
-    size_t expected_size = 0,     # Expected size of the solution. There is a slight performance improvement if selecting the the exact or slightly more time steps than the adaptive stepper will require (if you happen to know this ahead of time).
+    DiffeqFuncType diffeq_ptr,        # Differential equation defined as a cython function
+    double* t_span_ptr,               # Pointer to array (size 2) of floats defining the start and stop points for integration
+    double* y0_ptr,                   # Pointer to array defining initial y0 conditions.
+    unsigned int num_y,               # Size of y0_ptr array.
+    unsigned int method = 1,          # Integration method. Current options: 0 == RK23, 1 == RK45, 2 == DOP853
+    double rtol = 1.0e-3,             # Relative tolerance used to control integration error.
+    double atol = 1.0e-6,             # Absolute tolerance (near 0) used to control integration error.
+    void* args_ptr = NULL,            # Pointer to array of additional arguments passed to the diffeq. See "Advanced CySolver.md" for more details.
+    unsigned int num_extra = 0,       # Number of extra outputs you want to capture during integration. There is a performance hit if this is used in conjunction with t_eval or dense_output.
+    size_t max_num_steps = 0,         # Maximum number of steps allowed. If exceeded then integration will fail. 0 (the default) turns this off.
+    size_t max_ram_MB = 2000,         # Maximum amount of system memory the integrator is allowed to use. If this is exceeded then integration will fail.
+    bint dense_output = False,        # If True, then dense interpolators will be saved to the solution. This allows a user to call solution as if a function (in time).
+    double* t_eval = NULL,            # Pointer to an array of time steps at which to save data. If not provided then all adaptive time steps will be saved. There is a slight performance hit using this feature.
+    size_t len_t_eval = 0,            # Size of t_eval.
+    PreEvalFunc pre_eval_func = NULL  # Optional additional function that is called within `diffeq_ptr` using current `t` and `y`. See "Advanced CySolver.md" for more details.
+    double* rtols_ptr = NULL,         # Overrides rtol if provided. Pointer to array of floats of rtols if you'd like a different rtol for each y.
+    double* atols_ptr = NULL,         # Overrides atol if provided. Pointer to array of floats of atols if you'd like a different atol for each y.
+    double max_step = MAX_STEP,       # Maximum allowed step size.
+    double first_step = 0.0           # Initial step size. If set to 0.0 then CyRK will guess a good step size.
+    size_t expected_size = 0,         # Expected size of the solution. There is a slight performance improvement if selecting the the exact or slightly more time steps than the adaptive stepper will require (if you happen to know this ahead of time).
     )
 ```