PREDICT_TENSORFLOW_SCALAR
Applies an imported TensorFlow model on an input relation. This function, unlike PREDICT_TENSORFLOW, accepts one input column of type ROW, where each field corresponds to an input tensor, and returns one output column of type ROW, where each field corresponds to an output tensor.
For details about importing TensorFlow models into Vertica, see TensorFlow integration and directory structure.
Syntax
PREDICT_TENSORFLOW_SCALAR ( inputs
USING PARAMETERS model_name = 'model-name' )
Arguments
inputs
- Input column of type ROW with fields of 1D ARRAYs that represent input tensors. These tensors can represent outputs for various input operations.
Parameters
model_name
Name of the model (case-insensitive).
Examples
This function can simplify the process for making predictions on data with many input features.
For instance, the MNIST handwritten digit classification dataset contains 784 input features for each input row, one feature for each pixel in the images of handwritten digits. The PREDICT_TENSORFLOW function requires that each of these input features are contained in a separate input column. By encapsulating these features into a single ARRAY, the PREDICT_TENSORFLOW_SCALAR function only needs a single input column of type ROW, where the pixel values are the array elements for an input field:
--Each array for the "image" field has 784 elements.
=> SELECT * FROM mnist_train;
id | inputs
---+---------------------------------------------
1 | {"image":[0, 0, 0,..., 244, 222, 210,...]}
2 | {"image":[0, 0, 0,..., 185, 84, 223,...]}
3 | {"image":[0, 0, 0,..., 133, 254, 78,...]}
...
In this case, the function output consists of a single opeartion with one tensor. The value of this field is an array of ten elements, which are all zero except for the element whose index is the predicted digit:
=> SELECT id, PREDICT_TENSORFLOW_SCALAR(inputs USING PARAMETERS model_name='tf_mnist_ct') FROM mnist_test;
id | PREDICT_TENSORFLOW_SCALAR
----+-------------------------------------------------------------------
1 | {"prediction:0":["0", "0", "0", "0", "1", "0", "0", "0", "0", "0"]}
2 | {"prediction:0":["0", "1", "0", "0", "0", "0", "0", "0", "0", "0"]}
3 | {"prediction:0":["0", "0", "0", "0", "0", "0", "0", "1", "0", "0"]}
...
To view the expected input and output tensors for an imported TensorFlow model, call GET_MODEL_SUMMARY:
=> SELECT GET_MODEL_SUMMARY(USING PARAMETERS model_name='tf_mnist_ct');
GET_MODEL_SUMMARY
---------------------------------------------------------------------------
=============
input_tensors
=============
name |type |dimensions
-------+-----+----------
image |int32| [-1,784]
==============
output_tensors
==============
name | type |dimensions
--------------+------+----------
prediction:0 |int32 | [-1,10]
(1 row)