在这种情况下，我认为没有直接的方法可以告诉gnuplot如何解释输入.

I think there is no direct way of telling gnuplot of how to interpret the input in this case.

但是，您可以编写自己的函数，将字符串输入转换为数字

You can, however, write your own function that converts the string-input to numbers

check(x)=(pos=strstrt(x,"k"),\
    pos > 0 ? real(substr(x,1,pos-1))*1000  : real(x))

函数check首先确定字母'k'在输入中的位置. (如果输入x不包含字母'k'，则函数strstrt返回'0'.)
如果输入中包含字母"k"，请输入，丢弃最后一个字母，将剩余部分转换为数字，然后乘以1000. 如果输入不包含"k"，则返回输入

The function check first determines the position of the letter 'k' in the input. (The function strstrt returns '0' if the input x does not contain the letter 'k'.)
If the input contains the letter 'k', take the input, discard the last letter, convert the remaining part to a number and multiply it by 1000. If the input does not contain 'k', return the input

现在您可以绘制数据文件(假设其名称为test):

Now you can plot the data file (assuming its name is test):

plot 'test' u 1:(check(stringcolumn(2))) w l

这应该可以完成！