Fast radio bursts (FRBs) are intense radio transients whose physical origin remains unknown. Therefore, it is of crucial importance to use a model-independent method to obtain the energy function and cosmic formation rate directly from the observational data. Based on current samples from the Parkes and ASKAP telecsopes, we determine, for the first time, the energy function and formation rate of FRBs by using the Lynden-Bell ${\mathrm{C}}^{-}$ method. The energy function derived from the Parkes sample is a broken power law, however it is a simple power law for the ASKAP sample. For Parkes sample, we derive the formation rate which is roughly consistent with the star formation rate up to $z\sim 1.7$, with a local formation rate of $\dot{\rho }(0)\simeq (3.2\pm 0.3)\times {10}^4\mathrm{Gp}{\mathrm{c}}^{-3}\mathrm{y}{\mathrm{r}}^{-1}$ above a detection threshold of $2\mathrm{Jyms}$. For ASKAP sample, we find that the formation rate evolves much faster than the star formation rate up to $z\sim 0.7$, namely $\dot{\rho }(z)\propto {(1+z)}^{6.9\pm 1.9}$, with a local formation rate of $\dot{\rho }(0)\simeq (4.6\pm 0.8)\times {10}^3\mathrm{Gp}{\mathrm{c}}^{-3}\mathrm{y}{\mathrm{r}}^{-1}$ above a detection threshold of $51\mathrm{Jyms}$. This might be a important clue for the physical origin of FRBs.

快速无线电脉冲串（FRB）是强烈的无线电瞬变，其物理起源仍然未知。因此，使用独立于模型的方法直接从观测数据获得能量函数和宇宙形成速率至关重要。基于Parkes和ASKAP望远镜的当前样本，我们首次使用Lynden-Bell来确定FRB的能量函数和形成速率${\mathrm{C}}^{-}$方法。从帕克斯样本得出的能量函数是一个破坏的幂定律，但是对于ASKAP样本来说，它是一个简单的幂定律。对于派克斯（Parkes）样本，我们得出的形成速率与恒星形成速率大致一致，直至$ž〜1.7$，本地形成率是 $\dot{\rho }（0）\simeq （3.2\pm 0.3）\times {10}^4\mathrm{p}{\mathrm{C}}^{-3}\mathrm{ÿ}{\mathrm{[R}}^{-\mathrm{1个}}$ 高于检测阈值 $2\mathrm{吉姆斯}$。对于ASKAP样本，我们发现直到$ž〜0.7$，即 $\dot{\rho }（ž）\propto {（\mathrm{1个}+ž）}^{6.9\pm 1.9}$，本地形成率是 $\dot{\rho }（0）\simeq （4.6\pm 0.8）\times {10}^3\mathrm{p}{\mathrm{C}}^{-3}\mathrm{ÿ}{\mathrm{[R}}^{-\mathrm{1个}}$ 高于检测阈值 $51\mathrm{吉姆斯}$。这可能是FRB物理来源的重要线索。