Function LGBM_DatasetCreateFromCSRFunc 

pub unsafe extern "C" fn LGBM_DatasetCreateFromCSRFunc(
    get_row_funptr: *mut c_void,
    num_rows: c_int,
    num_col: i64,
    parameters: *const c_char,
    reference: DatasetHandle,
    out: *mut DatasetHandle,
) -> c_int

Create a dataset from CSR format through callbacks.

Arguments

• get_row_funptr - Pointer to std::function<void(int idx, std::vector<std::pair<int, double>>& ret)> (called for every row and expected to clear and fill ret)
• num_rows - Number of rows
• num_col - Number of columns
• parameters - Additional parameters
• reference - Used to align bin mapper with other dataset, nullptr means isn’t used
• out (direction out) - Created dataset

Returns

0 when succeed, -1 when failure happens