launch_mapdl

ansys.mapdl.core.launcher.launch_mapdl(exec_file=None, run_location=None, jobname='file', *, nproc=None, ram=None, mode=None, override=False, loglevel='ERROR', additional_switches='', start_timeout=None, port=None, cleanup_on_exit=True, start_instance=None, ip=None, clear_on_connect=True, log_apdl=None, remove_temp_dir_on_exit=False, license_server_check=False, license_type=None, print_com=False, add_env_vars=None, replace_env_vars=None, version=None, running_on_hpc=True, launch_on_hpc=False, **kwargs)

Start MAPDL locally.

Parameters:

exec_filestr, optional

The location of the MAPDL executable. Will use the cached location when left at the default None and no environment variable is set.

The executable path can be also set through the environment variable PYMAPDL_MAPDL_EXEC. For example:

export PYMAPDL_MAPDL_EXEC=/ansys_inc/v211/ansys/bin/mapdl

run_locationstr, optional

MAPDL working directory. Defaults to a temporary working directory. If directory doesn’t exist, one is created.

jobnamestr, optional

MAPDL jobname. Defaults to 'file'.

nprocint, optional

Number of processors. Defaults to 2. If running on an HPC cluster, this value is adjusted to the number of CPUs allocated to the job, unless the argument running_on_hpc is set to "false".

ramfloat, optional

Total size in megabytes of the workspace (memory) used for the initial allocation. The default is None, in which case 2 GB (2048 MB) is used. To force a fixed size throughout the run, specify a negative number.

modestr, optional

Mode to launch MAPDL. Must be one of the following:

• 'grpc'

• 'console'

The 'grpc' mode is available on ANSYS 2021R1 or newer and provides the best performance and stability. The 'console' mode is for legacy use only Linux only prior to 2020R2. This console mode is pending depreciation. Visit Versions and interfaces for more information.

overridebool, optional

Attempts to delete the lock file at the run_location. Useful when a prior MAPDL session has exited prematurely and the lock file has not been deleted.

loglevelstr, optional

Sets which messages are printed to the console. 'INFO' prints out all ANSYS messages, 'WARNING' prints only messages containing ANSYS warnings, and 'ERROR' logs only error messages.

additional_switchesstr, optional

Additional switches for MAPDL, for example 'aa_r', the academic research license, would be added with:

• additional_switches="-aa_r"

Avoid adding switches like -i, -o or -b as these are already included to start up the MAPDL server. See the notes section for additional details.

start_timeoutfloat, optional

Maximum allowable time to connect to the MAPDL server. By default it is 45 seconds, however, it is increased to 90 seconds if running on HPC.

portint

Port to launch MAPDL gRPC on. Final port will be the first port available after (or including) this port. Defaults to 50052. You can also provide this value through the environment variable PYMAPDL_PORT. For instance PYMAPDL_PORT=50053. However the argument (if specified) has precedence over the environment variable. If this environment variable is empty, it is as it is not set.

cleanup_on_exitbool, optional

Exit MAPDL when python exits or the mapdl Python instance is garbage collected.

start_instancebool, optional

When False, connect to an existing MAPDL instance at ip and port, which default to ip '127.0.0.1' at port 50052. Otherwise, launch a local instance of MAPDL. You can also provide this value through the environment variable PYMAPDL_START_INSTANCE. However the argument (if specified) has precedence over the environment variable. If this environment variable is empty, it is as it is not set.

ipstr, optional

Specify the IP address of the MAPDL instance to connect to. You can also provide a hostname as an alternative to an IP address. Defaults to '127.0.0.1'. Used only when start_instance is False. If this argument is provided, and start_instance (or its correspondent environment variable PYMAPDL_START_INSTANCE) is True then, an exception is raised. You can also provide this value through the environment variable PYMAPDL_IP. For instance PYMAPDL_IP=123.45.67.89. However the argument (if specified) has precedence over the environment variable. If this environment variable is empty, it is as it is not set.

clear_on_connectbool, optional

Defaults to True, giving you a fresh environment when connecting to MAPDL. When if start_instance is specified it defaults to False.

log_apdlstr, optional

Enables logging every APDL command to the local disk. This can be used to “record” all the commands that are sent to MAPDL via PyMAPDL so a script can be run within MAPDL without PyMAPDL. This argument is the path of the output file (e.g. log_apdl='pymapdl_log.txt'). By default this is disabled.

remove_temp_dir_on_exitbool, optional

When run_location is None, this launcher creates a new MAPDL working directory within the user temporary directory, obtainable with tempfile.gettempdir(). When this parameter is True, this directory will be deleted when MAPDL is exited. Default to False. If you change the working directory, PyMAPDL does not delete the original working directory nor the new one.

license_server_checkbool, optional

Check if the license server is available if MAPDL fails to start. Only available on mode='grpc'. Defaults False.

license_typestr, optional

Enable license type selection. You can input a string for its license name (for example 'meba' or 'ansys') or its description (“enterprise solver” or “enterprise” respectively). You can also use legacy licenses (for example 'aa_t_a') but it will also raise a warning. If it is not used (None), no specific license will be requested, being up to the license server to provide a specific license type. Default is None.

print_combool, optional

Print the command /COM arguments to the standard output. Default False.

add_env_varsdict, optional

The provided dictionary will be used to extend the MAPDL process environment variables. If you want to control all of the environment variables, use the argument replace_env_vars. Defaults to None.

replace_env_varsdict, optional

The provided dictionary will be used to replace all the MAPDL process environment variables. It replace the system environment variables which otherwise would be used in the process. To just add some environment variables to the MAPDL process, use add_env_vars. Defaults to None.

versionfloat, optional

Version of MAPDL to launch. If None, the latest version is used. Versions can be provided as integers (i.e. version=222) or floats (i.e. version=22.2). To retrieve the available installed versions, use the function ansys.tools.path.path.get_available_ansys_installations(). You can also provide this value through the environment variable PYMAPDL_MAPDL_VERSION. For instance PYMAPDL_MAPDL_VERSION=22.2. However the argument (if specified) has precedence over the environment variable. If this environment variable is empty, it is as it is not set.

running_on_hpc: bool, optional

Whether detect if PyMAPDL is running on an HPC cluster. Currently only SLURM clusters are supported. By default, it is set to true. This option can be bypassed if the PYMAPDL_RUNNING_ON_HPC environment variable is set to True. For more information, see Introduction to SLURM.

launch_on_hpcbool, Optional

If True, it uses the implemented scheduler (SLURM only) to launch an MAPDL instance on the HPC. In this case you can pass the ‘scheduler_options’ argument to launch_mapdl() to specify the scheduler arguments as a string or as a dictionary. For more information, see Introduction to SLURM.

kwargsdict, Optional

These keyword arguments are interface-specific or for development purposes. For more information, see Notes.

scheduler_optionsstr, dict

Use it to specify options to the scheduler run command. It can be a string or a dictionary with arguments and its values (both as strings). For more information visit Introduction to SLURM.

set_no_abortbool

(Development use only) Sets MAPDL to not abort at the first error within /BATCH mode. Defaults to True.

force_intelbool

(Development use only) Forces the use of Intel message pass interface (MPI) in versions between Ansys 2021R0 and 2022R2, where because of VPNs issues this MPI is deactivated by default. See Virtual private network (VPN) issues for more information. Defaults to False.

Returns:

Union[MapdlGrpc, MapdlConsole]

An instance of Mapdl. Type depends on the selected mode.

Return type:

Union[MapdlGrpc, MapdlConsole]

Notes

Ansys Student Version

If an Ansys Student version is detected, PyMAPDL will launch MAPDL in shared-memory parallelism (SMP) mode unless another option is specified.

Additional switches

These are the MAPDL switch options as of 2020R2 applicable for running MAPDL as a service via gRPC. Excluded switches not applicable or are set via keyword arguments such as "-j" .

-acc <device>

Enables the use of GPU hardware. See GPU Accelerator Capability in the Parallel Processing Guide for more information.

-amfg

Enables the additive manufacturing capability. Requires an additive manufacturing license. For general information about this feature, see AM Process Simulation in ANSYS Workbench.

-ansexe <executable>

Activates a custom mechanical APDL executable. In the ANSYS Workbench environment, activates a custom Mechanical APDL executable.

-custom <executable>

Calls a custom Mechanical APDL executable See Running Your Custom Executable in the Programmer’s Reference for more information.

-db value

Initial memory allocation Defines the portion of workspace (memory) to be used as the initial allocation for the database. The default is 1024 MB. Specify a negative number to force a fixed size throughout the run; useful on small memory systems.

-dis

Enables Distributed ANSYS See the Parallel Processing Guide for more information.

-dvt

Enables ANSYS DesignXplorer advanced task (add-on). Requires DesignXplorer.

-l <language>

Specifies a language file to use other than English This option is valid only if you have a translated message file in an appropriately named subdirectory in /ansys_inc/v201/ansys/docu or Program Files\ANSYS\Inc\V201\ANSYS\docu

-m <workspace>

Specifies the total size of the workspace Workspace (memory) in megabytes used for the initial allocation. If you omit the -m option, the default is 2 GB (2048 MB). Specify a negative number to force a fixed size throughout the run.

-machines <IP>

Specifies the distributed machines Machines on which to run a Distributed ANSYS analysis. See Starting Distributed ANSYS in the Parallel Processing Guide for more information.

-mpi <value>

Specifies the type of MPI to use. See the Parallel Processing Guide for more information.

-mpifile <appfile>

Specifies an existing MPI file Specifies an existing MPI file (appfile) to be used in a Distributed ANSYS run. See Using MPI Files in the Parallel Processing Guide for more information.

-na <value>

Specifies the number of GPU accelerator devices Number of GPU devices per machine or compute node when running with the GPU accelerator feature. See GPU Accelerator Capability in the Parallel Processing Guide for more information.

-name <value>

Defines Mechanical APDL parameters Set mechanical APDL parameters at program start-up. The parameter name must be at least two characters long. For details about parameters, see the ANSYS Parametric Design Language Guide.

-p <productname>

ANSYS session product Defines the ANSYS session product that will run during the session. For more detailed information about the -p option, see Selecting an ANSYS Product via the Command Line.

-ppf <license feature name>

HPC license Specifies which HPC license to use during a parallel processing run. See HPC Licensing in the Parallel Processing Guide for more information.

-smp

Enables shared-memory parallelism. See the Parallel Processing Guide for more information.

PyPIM

If the environment is configured to use PyPIM and start_instance is True, then starting the instance will be delegated to PyPIM. In this event, most of the options will be ignored and the server side configuration will be used.

Examples

Launch MAPDL using the best protocol.

>>> from ansys.mapdl.core import launch_mapdl
>>> mapdl = launch_mapdl()

Run MAPDL with shared memory parallel and specify the location of the Ansys binary.

>>> exec_file = 'C:/Program Files/ANSYS Inc/v231/ansys/bin/winx64/ANSYS231.exe'
>>> mapdl = launch_mapdl(exec_file, additional_switches='-smp')

Connect to an existing instance of MAPDL at IP 192.168.1.30 and port 50001. This is only available using the latest 'grpc' mode.

>>> mapdl = launch_mapdl(start_instance=False, ip='192.168.1.30',
...                      port=50001)

Run MAPDL using the console mode (not recommended, and available only on Linux).

>>> mapdl = launch_mapdl('/ansys_inc/v194/ansys/bin/ansys194',
...                       mode='console')

Run MAPDL with additional environment variables.

>>> my_env_vars = {"my_var":"true", "ANSYS_LOCK":"FALSE"}
>>> mapdl = launch_mapdl(add_env_vars=my_env_vars)

Run MAPDL with our own set of environment variables. It replace the system environment variables which otherwise would be used in the process.

>>> my_env_vars = {"my_var":"true",
    "ANSYS_LOCK":"FALSE",
    "ANSYSLMD_LICENSE_FILE":"1055@MYSERVER"}
>>> mapdl = launch_mapdl(replace_env_vars=my_env_vars)