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Find a suitable python cmd or give error if not possible

Source: R/find_python_cmd.r
find_python_cmd.Rd

find_python_cmd() finds a suitable python cmd or raises an error if not possible

Usage

find_python_cmd(
  minimum_version = NULL,
  maximum_version = NULL,
  required_modules = NULL,
  error_message = NULL
)

Arguments

minimum_version

The minimum version of python it should be. Should be a string with major and minor number separated by a .. If left NULL won't impose such a restriction.

maximum_version

The maximum version of python it should be. Should be a string with major and minor number separated by a .. If left NULL won't impose such a restriction.

required_modules

Which modules should be required. Can use a single | to represent a single either-or requirement like "json|simplejson". If left NULL won't impose such a restriction.

error_message

What error message the user will see if couldn't find a sufficient python binary. If left NULL will print out a default message.

Value

The path to an appropriate python binary. If such a path wasn't found then it will throw an error.

See also

can_find_python_cmd() for a wrapper which doesn't throw an error

Examples

try(find_python_cmd())
#> [1] "/usr/bin/python3.10"
try(find_python_cmd(minimum_version = "2.6", maximum_version = "2.7"))
#> Error in find_python_cmd(minimum_version = "2.6", maximum_version = "2.7") : 
#>   Couldn't find a sufficient Python binary. If you haven't installed the Python dependency yet please do so. If you have but it isn't on the system path (as is default on Windows) please add it to path or set options('python_cmd'='/path/to/binary')  or set the PYTHON, PYTHON2, or PYTHON3 environmental variables. Python must be at least version 2.6 Python must be at most version 2.7 
try(find_python_cmd(required_modules = c("argparse", "json | simplejson")))
#> [1] "/usr/bin/python3.10"