fixed slicing errors

                block_side = math.ceil(math.sqrt(block_size))

                # if side^2 > size - need to expand with something

                need_expanding = False 

                missing_in_block = 0

                if math.pow(block_side,2)>block_size:

                    need_expanding = True

                    missing_in_block = math.pow(block_side,2) - block_size

                tmp1 = []

                for i in range(layout[index]):

                    for j in range(blocks_number):

                        si = (j+0)*block_size

                        ei = (j+1)*block_size

                        # add expanding somewhere here:

                        # ...

                        tile = tf.reshape(wt[i,si:ei],shape=(block_side,block_side))

                        # wtm is expanded... only tested for 0

                        if missing_in_block!=0:

                            wtm = tf.concat(wt[i,si:ei],missing_in_block*[tf.reduce_min(w)])

                        else:

                            wtm = wt[i,si:ei]

                        tile = tf.reshape(wtm,shape=(block_side,block_side))

                        # stack to RGB

                        tiles = tf.stack([tile]*3,axis=2)

                        tiles = tf.concat([tiles, tf.expand_dims((block_side+0)*[grid],0)],axis=0)