Mailman 3 November 2018 - yt-users

MEMORY ERROR ACCESSING HIGHER AMR LEVELS
by Vadlamani Samhitha Nov. 5, 2018

Nov. 5, 2018

Hi, I'm encountering a memory issue when I try to access higher AMR levels of my simulation using arbitrary_grid. My simulation has a minimum level of 7 and maximum level 15. I'm accessing level 9 (corresponding to 512). > DIM=512 > > dd=ds.arbitrary_grid(left_edge= ds.arr([(com_x_1.value-30), > (com_y_1.value-30), (com_z_1.value-30)], 'kpc'), right_edge= > ds.arr([(com_x_1.value+30), (com_y_1.value+30), (com_z_1.value+30)], 'kpc'), > dims=[DIM,DIM,DIM]) > m=dd["gas", "cell_mass"].in_units('Msun') and I get: > Traceback (most recent call last): File "vel_disp.py", line 52, in <module> m=dd["gas", "cell_mass"].in_units('Msun') File > "/home/samvad/yt-conda/lib/python3.6/site-packages/yt/units/yt_array.py", > line 610, in in_units new_array = type(self)(self.ndview * conversion_factor, new_units) MemoryError Could someone please shed light on this? Am I accessing the levels in a wrong format? Is "dims" not corresponding to the absolute levels but the level differences? (as in the level 7 is considered to be level 0 in which case my maximum level would be 8)

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ACCESSING GAS FILEDS THROUGH ARBITRARY_GRID
by Vadlamani Samhitha Nov. 5, 2018

Nov. 5, 2018

Hi, I am using arbitrary_grid to access my data without flattening: > dd=ds.arbitrary_grid(left_edge=[(com_x_1.value-30), (com_y_1.value-30), > (com_z_1.value-30)]*kpc, right_edge=[(com_x_1.value+30), (com_y_1.value+30), > (com_z_1.value+30)]*kpc, dims=[128, 128, 128]) > and as I attempt to get the gas fields for this object, > print(dd['gas', 'velocity_x']) > but end up getting the error: (which isn't the case for deposit fields) yt.units.unit_registry.UnitParseError: Code units have not been defined. > Try creating the array or quantity using ds.arr or ds.quan instead. If I'm thinking right, is it because the arbitrary_grid is only applied to the particles. In that case, is there any equivalent for gas fields where I can access my 3D data for the gas as it is , without flattening? Thanks

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Checking how many cells with a particular condition
by Reju Sam John Nov. 1, 2018

Nov. 1, 2018

Dear all, I have the following derived field: h=0.702 @derived_field(name = "Name", take_log=False, units='g/s**3') def _Name(field, data): temp = data["Mach"].copy() temp.fill(0) ind = np.where(((data['dx']*128*1000)*(1+z)*h<100)) temp[ind]= 0.5*data["Density"][ind]*(data["Mach"][ind]*data["SoundSpeed"][ind])**3 return temp How to check that, how many cells with cell size less than 100 kpc ( data['dx']*128*1000)*(1+z)*h<100) ? thankyou -- Reju Sam John

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