In the above question I see that you haven't provided any target data(classification labels) for training the network.
To use an image datastore as a source of training data, use the imds argument of trainNetwork. To use all other types of datastore as a source of training data, use the ds argument of trainNetwork. To be a valid input for training or validation, the read function of a datastore (with the exception of ImageDatastore) must return data as either a cell array or a table.
For networks with a single input, the table or cell array returned by the datastore must have two columns. The first column of data represents inputs to the network and the second column of data represents responses. Each row of data represents a separate observation.
In case of input size 2x1 & a table, it should be something like below:
>>>data = read(ds)
data =
4×2 table
input response
______________ ________
{2×1 double} 7
{2×1 double} 7
{2×1 double} 9
{2×1 double} 9
