Wrong grid "properties" and units of field

[jhornung-gh]

It seems like there is a bug with the properties of the fields like e_x, e_y, e_z, which don't match the expected values, specifically the grid_global_offset, grid_spacing, grid_unit_SI and unit_dimension. Same occurs for scalar fields such as the density, etc.

Here is an example of the electric field (Currently e_x which should be changed to E with the corresponding dimension according to issue #7):

Converted properties:

grid_global_offset: [0.0] (depending on the dimension [x_offset, y_offset, z_offset])
grid_spacing: [1.0] (depending on the dimension [dx, dy, dz])
grid_unit_SI: 1.0
unit_dimension: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

Expected properties (rounded):
grid_global_offset: [-10000]
grid_spacing: [5.0]
grid_unit_SI: 1.0e-9
unit_dimension: [1.0, 1.0, -3.0, -1.0, 0.0, 0.0, 0.0]

However, I have to admit that I am not sure how the grid_unit_SI is determined since this can also have an "odd" number like 8.5164e-9.

[denisbertini]

i understood the expected value properties besides of :

• global offset [-10000] ?

[jhornung-gh]

basically -10000 nanometers (unit SI conversion), e.g. -10 µm offset of the first pixel. My simulation box starts at x= -10 µm.

[denisbertini]

But are you sure that this is what is meant by global offset ?

[jhornung-gh]

not 100%, but there is no other property which corresponds to the grid offset, or is there any?

Maybe I missed something here, I will have another look at it.

[denisbertini]

No idea for now, one will have to look carefully at ALL the attributes that goes to the converted files and eventually add those which are missing ... this is a work in progress as you see ...

[jhornung-gh]

One issue from my side: The grid_unit_SI has to be 1.0 since EPOCH already handles everything in SI units and the corresponding grid_spacing should then be 5e-9. This only has to differ from 1.0 if non-SI units are used. Regarding the grid_global_offset I am still not sure but I don't see any other attribute defining where the x- and y-axis starts.

[denisbertini]

i will look at the definition of these attribute more in details, i have to confess that i did not really check these up to now

[denisbertini]

This should be now solved with the commit 0ea8b0672bf0b17a4998f27ffe9428688eb82c82