NEK5000 utilities for MATLAB (first release)

NEK5000 utilities for MATLAB

Jacopo Canton and Nicolò Fabbiane (in alphabetical order)

January, 2016

Functions

readnek.m

This function reads binary data from the nek5000 file format

[data,lr1,elmap,time,istep,fields,emode,wdsz,etag,header,status] = readnek(fname)

input

• fname: name of the file

output

• data: nek5000 data ordered as {iel,inode,[x|y|(z)|u|v|(w)|p|T|s_i]}
• lr1: element-size vector [lx1,ly1,lz1]
• elmap: reading/writing map of the elements in the file
• time: simulation time
• istep: simulation step
• fields: fields saved in the file
• emode: endian mode 'le' = little-endian, 'be' = big-endian
• wdsz: single (4) or double (8) precision
• etag: tag for endian indentification
• header: header of the file (string)
• status: status (< 0 something went wrong)

writenek.m

This function writes binary data in the nek5000 new file format

status = writenek(fname,data,lr1,elmap,time,istep,fields,emode,wdsz,etag)

input

• fname: name of the file
• data: nek5000 data ordered as {iel,inode,[x|y|(z)|u|v|(w)|p|T|s_i]}
• lr1: element-size vector [lx1,ly1,lz1]
• elmap: reading/writing map of the elements in the file
• time: simulation time
• istep: simulation step
• fields: fields saved in the file
• emode: endian mode 'le' = little-endian, 'be' = big-endian
• wdsz: single (4) or double (8) precision
• etag: tag for endian indentification

output

• status: status (< 0 something went wrong)

reshapenek.m

Reshape data from nekread to a meshgrid

[mesh1,mesh2,...] = reshapenek(data,nelx,nely)

input

• data: nek5000 data ordered as {iel,inode,[x|y|(z)|u|v|(w)|p|T|s_i]}
• nelx: number of element in the first direction (second index)
• nely: number of element in the second direction (first index)

output

• meshn: meshgrid of the n-th field in data

demeshnek.m

Demesh a meshgrid to data

[data] = reshapenek(mesh,lr1)

input

• mesh: meshgrid (fields along third index)
• lr1: element-size vector [lx1,ly1,lz1]

output

• data: nek5000 data ordered as {iel,inode,[x|y|(z)|u|v|(w)|p|T|s_i]}

This package has been also tested with Octave.