python - Database Design for Covariance Matrix (constant size, diagonally symmetric) -


i'm new realm of relational database design, , trying store 9x9 covariance matrix in table. rows , columns x, y, z terms of position, velocity, , acceleration. so:

        posx posy posz . . . accz       ------------------------- posx  |  xx   xy   xz  . . . posy  |  yx   yy   yz  . . .  posz  |  zx   zy   zz  . . .  .     |  .    .    . .     |  .    .    . .     |  .    .    . accz  |

so instance, upper-left element posxposx (shortened xx above), right posxposy, , on. matrix symmetric along diagonal (i.e. posxposy == posyposx). it's possible want store 6x6 matrix includes position , velocity in same table.

from research, i've found normalized table design of creating table fields row number, column number, , value (how represent 2-d data matrix in database). can see benefit flexibility, since number of rows , columns can variable. best way proceed, though have set number of rows , columns (9x9 and/or 6x6)? envision creating table has fields each unique row/col combination (posxposx, posxposy . . . etc). seems more intuitive me, said i'm new @ this.

my question is: how suggest representing data in relational database? i've outlined 2 possible methods don't know if either best way. "best" in case mean efficiently stored , retrieved. i'm creating data repository, data in database not changing once added, read numpy arrays or similar.

some more background:
i'm analyzing test data. have multiple test runs different configurations, each having multiple data points include lot of different kinds of data. 1 of data points want store , analyze covariance. amount of data i'm dealing quite staggering, i'm hoping using database me keep things organized , accessible. goal store data, , write data analysis , visualization tools draw data. in case of covariance, i'm calculating things mahalanobis distance, trace, , time propagated eigenvalues. have many of these tools already, pull lot of different log files , mess.

as long data-set small , can assume values once read not modified external application, might worth considering using csv file , read data whatever data structure useful while doing analysis. let @ data easier because need text editor or if wanted way view spreadsheet.

based on have said, seems cleanest thing have 1 record per cell because give flexibility in future. if interested in reading database design this pretty starting place

one possible design be:

table matrix(record_id, parent_id, matrix_id, x, y, value)

where record_id uniquely identifies record, parent_id reference owning entity matrix, matrix_id uniquely identifies elements in matrix,x , y coordinates record , value cell value.

then query like:

select *      matrix matrix_id=? order x asc, y asc

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