.. _quick_start_HEM_v0.36_FHS_v0.27: Quick Start =========== The HEM help guide ------------------ Once HEM is installed, we can view the help guide of the `hem.py `__ module using ``-h`` or ``--help`` argument. Use one of the following command prompts (they do the same thing): * ``python [PATH_TO_HEM_ROOT_DIRECTORY]\src\hem.py -h`` * ``python [PATH_TO_HEM_ROOT_DIRECTORY]\src\hem.py --help`` This prints the following help text: .. code-block:: bash usage: hem.py [-h] [--epw-file EPW_FILE] [--CIBSE-weather-file CIBSE_WEATHER_FILE] [--tariff-file TARIFF_FILE] [--parallel PARALLEL] [--preprocess-only] [--future-homes-standard | --future-homes-standard-FEE | --future-homes-standard-notA | --future-homes-standard-notB | --future-homes-standard-FEE-notA | --future-homes-standard-FEE-notB] [--heat-balance] [--detailed-output-heating-cooling] [--no-fast-solver] [--display-progress] [--no-validate-json] input_file [input_file ...] Home Energy Model (HEM) positional arguments: input_file path(s) to file(s) containing building specifications to run options: -h, --help show this help message and exit --epw-file EPW_FILE, -w EPW_FILE path to weather file in .epw format --CIBSE-weather-file CIBSE_WEATHER_FILE path to CIBSE weather file in .csv format --tariff-file TARIFF_FILE path to tariff data file in .csv format --parallel PARALLEL, -p PARALLEL run calculations for different input files in parallel(specify no of files to run simultaneously) --preprocess-only run prepocessing step only --future-homes-standard use Future Homes Standard calculation assumptions --future-homes-standard-FEE use Future Homes Standard Fabric Energy Efficiency assumptions --future-homes-standard-notA use Future Homes Standard calculation assumptions for notional option A --future-homes-standard-notB use Future Homes Standard calculation assumptions for notional option B --future-homes-standard-FEE-notA use Future Homes Standard Fabric Energy Efficiency assumptions for notional option A --future-homes-standard-FEE-notB use Future Homes Standard Fabric Energy Efficiency assumptions for notional option B --heat-balance output heat balance for each zone --detailed-output-heating-cooling output detailed calculation results for heating and cooling system objects (including HeatSourceWet objects) where the relevant objects have this functionality --no-fast-solver disable optimised solver (results may differ slightly due to reordering of floating-point ops); this option is provided to facilitate verification and debugging of the optimised version --display-progress display progress for the json input file currently running --no-validate-json disable JSON schema validation (useful during development) This tells us that when calling the `hem.py `__ module, we should provide the ``input_file`` argument (as it is a 'positional argument') and we can also supply many different options arguments (``-h``, ``--epw-file``, ``--CIBSE-weather-file`` etc.). What do all these arguments do? This doesn't seem to be documentented anywhere but we can make reasonable guesses given the descriptions above. .. _an_example_simulation_HEM_v0.36_FHS_v0.27: An example simulation --------------------- This simulation uses: * the `demo.json `__ input file from the HEM repository. * the `London_weather_CIBSE_format.csv `__ weather data file from the HEM repository. The steps are: 1. Save the *demo.json* and *London_weather_CIBSE_format.csv* files in the same folder on your local computer. 2. Open the Command Prompt. 3. Change the directory of the Command Prompt to where the files are stored using ``cd [PATH_TO_MY_DIRECTORY]``. 4. Run the prompt: ``python [PATH_TO_HEM_ROOT_DIRECTORY]\src\hem.py --CIBSE-weather-file London_weather_CIBSE_format.csv demo.json``. * ``python`` calls the Python interpreter. * ``[PATH_TO_HEM_ROOT_DIRECTORY]`` is the directory where the HEM repository is stored on your computer. Please replace this text with the local path you have used. * ``src\hem.py`` is the path to Python module `hem.py `__ which provides the point of access to the HEM calculations. * ``--CIBSE-weather-file`` is the CIBSE weather data flag as described in the help text above. * ``London_weather_CIBSE_format.csv`` is the filepath to the CIBSE weather file (this must follow directly after ``--CIBSE-weather-file``). * ``demo.json`` is the filepath to the input file. This results in the following text printed in the Command Prompt. .. code-block:: Running 1 cases in series This also creates a new subfolder named *demo__results* (the name of the input file plus '__results') which contains the following results files: * *demo.json* * *demo__core__results.csv* * *demo__core__results_static.csv* * *demo__core__results_summary.csv*