Python uses plt Plot plot bar graph abscissa scale is set to integer

In the use of python When processing audio signals , Use plt.plot When plotting histogram , You want the abscissa to be an integer , I.e. audio channel number , The method commonly used is ：

xticksig = np.arange(1,1+MicNum)

Or add a step to it ：

xticksig = np.arange(1,1+MicNum,1)

However, the abscissa obtained by these two methods has decimals , As shown in the figure below ：

The correct usage should be as follows ：

xticksig = np.arange(1,1+MicNum).astype(dtype=np.str)

The results are shown in the figure below , Abscissa has no decimals , Only integer ：