Inquire if a GMT common option has been set and return its current value if possible.


option (str) – The GMT common option to check. Valid options are "B", "I", "J", "R", "U", "V", "X", "Y", "a", "b", "f", "g", "h", "i", "n", "o", "p", "r", "s", "t", and ":".


value (bool, int, float, or numpy.ndarray) – Whether the option was set or its value.

If the option was not set, return False. Otherwise, the return value depends on the choice of the option.

  • options "B", "J", "U", "g", "n", "p", and "s": return True if set, else False (bool)

  • "I": 2-element array for the increments (float)

  • "R": 4-element array for the region (float)

  • "V": the verbose level (int)

  • "X": the xshift (float)

  • "Y": the yshift (float)

  • "a": geometry of the dataset (int)

  • "b": return 0 if -bi was set and 1 if -bo was set (int)

  • "f": return 0 if -fi was set and 1 if -fo was set (int)

  • "h": whether to delete existing header records (int)

  • "i": number of input columns (int)

  • "o": number of output columns (int)

  • "r": registration type (int)

  • "t": 2-element array for the transparency (float)

  • ":": return 0 if -:i was set and 1 if -:o was set (int)


>>> with Session() as lib:
...     lib.call_module("basemap", "-R0/10/10/15 -JX5i/2.5i -Baf -Ve")
...     region = lib.get_common("R")
...     projection = lib.get_common("J")
...     timestamp = lib.get_common("U")
...     verbose = lib.get_common("V")
...     lib.call_module("plot", "-T -Xw+1i -Yh-1i")
...     xshift = lib.get_common("X")  # xshift/yshift are in inches
...     yshift = lib.get_common("Y")
>>> print(region, projection, timestamp, verbose, xshift, yshift)
[ 0. 10. 10. 15.] True False 3 6.0 1.5
>>> with Session() as lib:
...     lib.call_module("basemap", "-R0/10/10/15 -JX5i/2.5i -Baf")
...     lib.get_common("A")
Traceback (most recent call last):
pygmt.exceptions.GMTInvalidInput: Unknown GMT common option flag 'A'.