Changing BDF PARAM

[kay]

Hi,

I have a problem in changing solver PARAM values in the BDF files. I did not find anything useful in the documentation.

My goal:

change PARAM       POST       0

to PARAM       POST       -1

BDF.params seems to give access to the parameters:

$ print  BDF.params

{'POST': $ Direct Text Input for Bulk Data

PARAM       POST       0

, 'PRTMAXIM': PARAM   PRTMAXIM     YES

}

What I tried:

BDF.params["POST"].value = -1

but this did not change anything, as the output of BDF.params stays the same.

$ print  BDF.params

{'POST': $ Direct Text Input for Bulk Data

PARAM       POST       0

, 'PRTMAXIM': PARAM   PRTMAXIM     YES

}

I can change the string in BDF.params["POST"] but I'd rather use dedicated methods to set values.

I also tried 

newPARAM = pyNastran.bdf.cards.params.PARAM

newPARAM.key = "POST"

newPARAM.value = -1

BDF.add_PARAM(newPARAM, allowOverwrites=True)

but this adds the obejct to the value, whicht of course does not work:

$ print  BDF.params

{'POST': <class 'pyNastran.bdf.cards.params.PARAM'>

, 'PRTMAXIM': PARAM   PRTMAXIM     YES

}

Thanks for any input,

kay

[steve]

There's are bugs in the code that was introduced in v0.6 to support PARAM cards with multiple fields.  I need to push a bug release anyways, so that'll be in there.

In the current version of the code, the correct way to change the parameter is:

BDF.params["POST"].values[0] = -1

I'm updating the code to allow:

BDF.params["POST"].update_values(value1, value2=None)

as well as (broken in v0.6.1):

card = None

data = ['POST', -1]

newPARAM = PARAM(card, data, comment='')

BDF.params['POST'] = newPARAM

Additionally, as changing the self.value parameter does not properly update the self.values list of parameters, self.value will be removed (as well as self.value1 and self.value2 for length=2 PARAMs).

Steve

[kay]

Very well!

I wasn't aware which values/lists are used to update and which ones are just representations.

Removing redundant values and having a method that updates everything would be nice.

Thank you Steve!

[kay]

Just an additional info for users that want to add PARAMS in version v0.6.1 (broken according to Steve) :

A workaround is to use an existing param, then modify it and add it to the BDF.params.

Example to add: PARAM, BUCKLING, 1 

# deepcopy and existing param card

param = copy.deepcopy(BDF.params["POST"])

# set the key and value of this card

param.key = 'BUCKLING'

param.value = 1

# add the card to BDF.params

BDF.params['BUCKLING'] = param