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Tables are the basical metadata system in Dynamo. They are just matrices that describe the properties of sets of particles. The property coded on each column is fixed.

A table can be seen as the metadata of a given data folder. The first column in a table is just an integer number (which we call a tag) that identifies a particle. In the data folder, this particle is identified by the name of the file that contains it, i.e.

<myData>/particle_00003.em would be the particle with tag 3 in the data folder myData. A table will be able to operate on this particle if it has a row whose first column is the integer 3.

As Tables are matrices, Matlab tools (like find,plot,hist) are easily customizable to explore and visualize the contents of a table. Additionally, Dynamo includes many specific utilities. dapropos table will give you a list of basic commands that you can use for table manipulation.

Format convention in a table

Template:Table Convention

The convention can be consulted each time by the command dthelp

Reading and writing tables

Tables are customarily stored as text files with extension '.tbl'.

Tables can be read and write into the matlab worspace with the standard commands dwrite and dread.

For specially long tables, you can use the extension '.tbl', which will write the files in binary format, allowing considerable speedup in I/O.

Visualization of tables

Basic info

dtinfo dinfo table just plots on screen a summary of the contents of the table on each column.

Command line dtplot

[[ dtplot]] allows the creation of graphs like: positions of particles in a volume, orientations, distributions of orientations. One example of use of the command is to check if all the particles in a reference (column = 34) have a similar missing wedge orientation (the tilt angle is coded in column 8).

GUI for Basic plots

[[ dtshow]] dtshow table opens a lightweight GUI that allows quick plotting of the contents of the table, and also a GUI access to all the plotting options of dtplot

GUI for complex plots dtview

[[ dtview]] is a more complicated browser for table contents, allowing the joint visualization of pairs of properties for particle sets inside a table.

Table manipulation

Creating tables

In general, Dynamo itself creates correctly formatted tables as they are needed. If a table needs to be explicitly created, an easy way to create a blank table compatible with a given data folder is with the command dynamo_table_blank.

Selection of parts of a table

Use dtgrep. It's applicability ranges from just selecting an explicitely defined range of particle tags to the computation of particles pointing in a direction.

Conversion tools for other software packages

dapropos compatibility will print a selection of functions that can be used to import and export particle metadata with the format expected by other packages, as AV3, jsubtomo and XMIPP