title: Create random trainable indices to build two 2_D tensor from one 2_D tensor in tensorflow
body: <p>I'm trying to create two tensors with shape <strong>shape=(30, 4200)</strong> from one tensor <strong><em>AAA</em></strong> with shape=(30, 4201)and type= float32.</p>
  
  <p>This error will appear again after running the code with several different changes.</p>
  
  <p>How do I select the correct tensor shape?</p>