openNetOutputFile - begins writing network output activations to a file

### USAGE

        openNetOutputFile <file-name> [-binary | -append]

### DESCRIPTION

This command opens the network's output file. Subsequently, each time an example is run during training, testing, or using doExample, the outputs and possibly target values of selected groups will be written to the file. This allows the network's performance to be saved and custom-analyzed.

The values written to the file are taken from the history arrays of groups that have the WRITE_OUTPUTS type. If the group is also of type OUTPUT, both the output and target values are written, otherwise only outputs are written. By default, output groups are given the WRITE_OUTPUTS type, but other groups are not.

Because the values are taken from the output or target history array once the example is done, the values will not be accurate unless those arrays are filled in. If you are using a non-continuous network and do not have the Unit Viewer open, Lens may not fill in the history array to save time. To force Lens to use the history arrays, add USE_OUTPUT_HIST and USE_TARGET_HIST to the types of the groups.

Ordinarily, if the file already exists, it will be overwritten. But if the -append option is used, the output will be appended to the specified file. If a file is already open from a previous openNetOutputFile call, it will be closed before opening the new file. The exception to this is if the -append flag is used and the open file and the new file have the same name, in which case the file simply remains open.

It is best to close files with the closeNetOutputFile when you are done writing to them. File names ending in .gz, .bz, .bz2, or .Z will automatically be compressed.

By default, files are written in text format. The -binary flag will cause outputs to be written in binary.

Customarily, output record files end in ".or" or ".out".

### EXAMPLES

To begin saving outputs in the compressed binary file "foo.or.gz":

        lens> openNetOutputFile foo.or.gz -b

### SEE ALSO

closeNetOutputFile, train, test, doExample

Last modified: Mon Nov 20 13:26:32 EST 2000