Get extent of gridpoints

FLAC3D
1

Hi,
any hint for how to get the values for minimum and maximum gp extent via a fish command?
I can read them using the ‘zone list summary’ command

flac3d>zone list summary
    Number of Gps : 336633
Maximum Gp Extent : (4.66635000e+05,6.56261700e+06,-1.20501872e+02)
Minimum Gp Extent : (4.61635000e+05,6.55761700e+06,-3.00000000e+03)
Maximum Gp Displ. : 0.00000000e+00
  Number of Zones : 320000
 Max. Zone Volume : 5.32443736e+05
 Min. Zone Volume : 9.28385223e+03
 Max. Zone Stress : 0.00000000e+00
 Min. Zone Stress : 0.00000000e+00
  Number of Attaches : 0
Number of Interfaces : 0

But would like to get them dynamically.
Thanks,
Julia

2

Hi @JuDi !

A Fish function relying on gridpoint functions would be:

def get_extent
    local xmin = 1e12 ; A really huge value
    local ymin = xmin 
    local zmin = xmin 
    local xmax = -1e12 ; A really small value
    local ymax = xmax 
    local zmax = xmax 
    loop foreach local gppnt gp.list
        xmin = math.min(xmin, gp.pos(gppnt)->x)
        ymin = math.min(ymin, gp.pos(gppnt)->y)
        zmin = math.min(zmin, gp.pos(gppnt)->z)
        xmax = math.max(xmax, gp.pos(gppnt)->x)
        ymax = math.max(ymax, gp.pos(gppnt)->y)
        zmax = math.max(zmax, gp.pos(gppnt)->z)
    end_loop
    get_extent = list.seq(vector(xmin,ymin,zmin), vector(xmax,ymax,zmax))
end

Then, running the command [extent = get_extent] in Flac3D console will store 2 vectors in the extent variable: extent(1) is the vector with minimum x, y, and z of gridpoints, and extent(2) stores the max values.

Another option would be to use splitting:

def get_extent2
    local extent_min = vector(list.min(gp.pos(::gp.list)->x),list.min(gp.pos(::gp.list)->y),list.min(gp.pos(::gp.list)->z))
    local extent_max = vector(list.max(gp.pos(::gp.list)->x),list.max(gp.pos(::gp.list)->y),list.max(gp.pos(::gp.list)->z))
    get_extent2 = list.seq(extent_min, extent_max)
end

Alternatively, you could take advantage of the Python API. In a Python console, this should do the trick:

import itasca as it

# Contains xmin, ymin, zmin
min_ext = it.gridpointarray.pos().min(axis=0)
# Contains xmax, ymax, zmax
max_ext = it.gridpointarray.pos().max(axis=0)

Cheers!

Théophile

1 Like
3

Hi Théophile,

very much appreciated. I was hoping for something like the splitting to avoid the looping over all grid points. Great!
Julia

4

Glad it helped!

Splitting is powerful indeed!
It might not be the fastest one, though, if performance matters (see multithreading section on official page).

Cheers

Théophile