====== P2D Format ======

The P2D file format was part of the original MOVE3D software written, which formed the basis of Visual3D. This file format can still be imported by Visual3D to provide backwards compatibility with legacy data at the NIH, to summarize a normal database, and for creating ”odd-ball” graphics overlaid on report graphs.

==== P2D Signals ====

Originally, P2D Files were opened in Visual3D and stored in the GLOBAL folder of the Visual3D workspace as P2D signals.

These signals retained the same format as the P2D files, and we treat P2D File and P2D Signal synonymously.

The original P2D files contains the mean and standard deviation components of a signal. In keeping with this tradition, the [[Visual3D:Documentation:Pipeline:Signal_Commands:Global_Normalized_Signal_Mean|Global_Normalized_Signal_Mean]] command produces P2D signals as well.

==== Format ====

Any laboratory can create a series of P2D files that represent their normative data. If the user opens all P2D files at once and saves a [[Visual3D:Documentation:Definitions:File_Formats:CMZ_Format_|CMZ file]], the CMZfile will contain all of the P2D data signals in a single file.

The P2D file is a text file that contains a simple header and data section. The header (first) record of the P2D file contains three integers separated by a space. The first integer is the number of data entries (or rows), the second integer is the number of ordinate columns and the third integer is always zero.

For example:
15 2 0
The columns of the output P2D files are separated by blank spaces. Each column contains the same number of rows.
For Example: two frames of data are represented by two rows.
0 1
1 1.1
Each column is a component in the P2D signal. For example, 5 columns of data represents a signal with 5 components.

Using the file:open menu option it is possible to open p2d data. A signal is created in Visual3D with the same name as the p2d filename on disk. For a variety of historical and technical reasons, p2d data does not appear in the data tree (in Event Processing Mode). The only way to get access to p2d data is when you are generating a report graph.

P2d data must be displayed against itself (e.g. element 1 vs element 2).

**P2D File Format**

15 2 0
1 0
2 15.3774
3 10.6582
4 6.2569
5 2.9658
6 1.0071
7 0.1427
8 -0.0545
9 0.0276
10 0.1536
11 0.2424
12 0.2803
13 0.2677
14 0.2041
==== Example containing mean and standard deviation ====

A common use of the P2D format is for storing the mean and standard deviation data for one signal (e.g. from normative data). In the following example a p2d file containing time normalized data (51 points) for the mean and standard deviation will appear as:

51 2 0\\
1.000000 -0.171476 0.064203\\
2.000000 -0.193810 0.052127\\
3.000000 -0.194081 0.107100\\
4.000000 -0.150445 0.121488\\
5.000000 -0.059907 0.087786\\
6.000000 0.042586 0.043269\\
7.000000 0.118689 0.035538\\
8.000000 0.156265 0.050328\\
9.000000 0.172037 0.062839\\
10.000000 0.183095 0.067463\\
11.000000 0.194891 0.070898\\
12.000000 0.204698 0.078152\\
13.000000 0.211091 0.088810\\
14.000000 0.215793 0.098449\\
15.000000 0.220938 0.103864\\
16.000000 0.225731 0.104650\\
17.000000 0.228312 0.102229\\
18.000000 0.228412 0.098830\\
19.000000 0.227623 0.095728\\
20.000000 0.227414 0.093014\\
21.000000 0.227485 0.089656\\
22.000000 0.226159 0.085224\\
23.000000 0.221815 0.080099\\
24.000000 0.215041 0.075135\\
25.000000 0.207752 0.070403\\
26.000000 0.201338 0.066043\\
27.000000 0.195480 0.061912\\
28.000000 0.189448 0.057273\\
29.000000 0.183203 0.051364\\
30.000000 0.176926 0.044302\\
31.000000 0.170491 0.037066\\
32.000000 0.163738 0.030801\\
33.000000 0.156836 0.026320\\
34.000000 0.150075 0.023576\\
35.000000 0.143514 0.022056\\
36.000000 0.137175 0.021138\\
37.000000 0.130963 0.020152\\
38.000000 0.124659 0.018674\\
39.000000 0.117935 0.016824\\
40.000000 0.110651 0.015405\\
41.000000 0.102797 0.015020\\
42.000000 0.094458 0.015891\\
43.000000 0.085670 0.017849\\
44.000000 0.076587 0.020574\\
45.000000 0.067596 0.023515\\
46.000000 0.059138 0.026223\\
47.000000 0.051278 0.028302\\
48.000000 0.043641 0.029549\\
49.000000 0.035876 0.029884\\
50.000000 0.028065 0.029869\\
51.000000 0.020488 0.030334

==== Graphing P2D Signals ====

When a P2D file is opened in Visual3D it is stored in the GLOBAL Workspace. The signals can be graphed in a Report Graph by selecting the type to be p2d.

A typical graph would have component 1 on the x-axis, component 2 on the y axis, and component 3 as the standard deviation.\\
{{:p2dReportGraph.gif}}\\