Matplotlib error: Value Error: x and y must have same first dimension

[Oscar Benjamin]

On 13 November 2015 at 08:34, Laura Creighton <lac at openend.se> wrote:
> In a message of Thu, 12 Nov 2015 17:54:28 -0800, Abhishek writes:
>>I am trying to run some Python code for the last few hours. How can I achieve the effect of "dot divide" from Matlab, in the following code? I am having trouble working with list comprehension and numpy arrays and getting the following error:
>>
>>    Traceback (most recent call last):
>>      File "Thurs.py", line 128, in <module>
>>        plt.plot(np.array(range(1,N/2+2)), Splot[alpha][iii,val]/utot[iii,val],color=cmap(iii/50))
>>
>>    ValueError: x and y must have same first dimension
>
> Splot is a list.  matplotlib wants 2 numpy arrays.  You have to cast
> it with np.array() too.

Actually the plot command is perfectly happy converting lists or lists
of lists etc. to arrays (by calling np.array internally) so you don't
need to convert any of your inputs. By the way: np.arange(1, N/2+2)
would be the usual way to create a numpy array that is a range.

The error here comes because (after both arguments are converted to
arrays) they have incompatible sizes. In other words:

    len(range(1,N/2+2)) != len(Splot[alpha][iii,val]/utot[iii,val])

I'm not sure what the solution is as the code is too complex for me to
spend time trying to guess what it's trying to do.

--
Oscar