CDAW-9.2 User's Guide Version 2.0
[Original was a MS Word document dated 11/28/89. VAX version made 12/29/93.]
[Page numbers here were inserted to match the original printed version.]
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WELCOME TO THE
CDAW-9
DATABASE AND DATABASE ANALYSIS
SOFTWARE SYSTEM!
The following "User's Guide" is structured as a tiered, tutorial introduction
for YOUR access to and use of the CDAW-9 database. In it, we will attempt to
present the overall "system" (database plus associated access/analysis
software) as one tool in the CDAW (Coordinated Data Analysis Workshop) program.
The following sections are thus organized as examples and tutorials rather than
as a true reference guide.
Some familiarity with the VAX/VMS user commands is helpful. If you are
completely unfamiliar with VMS, please see the NSSDC publication #88-21,
"A Beginner's Guide to Using the NSSDC VAX Computer System." Other specific
features of VMS potentially relevant to CDAW participants (e.g., VMS
subdirectories) will be discussed later in this series of tutorials.
Questions or comments on this writeup or the CDAW program should be
directed to:
Dr. Robert E. McGuire PHONE: 301-286-7794
National Space Science Data Center SPAN: NCF::MCGUIRE
Code 633 TELEMAIL:
NASA/Goddard Space Flight Center [RMCGUIRE/GSFCMAIL] GSFC
Greenbelt, MD 20771 USA
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TABLE OF CONTENTS
I. GETTING STARTED: AN OVERVIEW 1
II. GETTING STARTED: A SIMPLE GRAPHICS EXAMPLE 3
II.A. Invoking the CDAW Software 3
II.B. Data Management Selection/Summary Screen: 6
II.C. CDAW (XY/Panel Graphics) Summary Screens: 12
II.C.1. Graphics Summary Screen - Control Page 15
II.C.2. Graphics Summary Screen - Specification Page 19
II.D And Here Comes the Plot! 25
II.D.1. Now that you have a plot displayed: 26
II.D.2. To re-enter the XY/Panel Summary screens: 27
II.D.3. If you wish to interrupt this tutorial at this point: 27
II.D.4. When you wish to resume this tutorial: 27
III. NOW THAT YOU'VE STARTED: A CONTINUATION OF THE GRAPHICS
TUTORIALS 28
III.A. Completing the Graphics Goals of the Preceding Section 28
III.B Creating Paper or Transparency Copies of Plots 30
III.C. Saving Things: Save/Restore Options, VMS Subdirectories
and the CDAW Purge/Delete Options: 32
III.C.1. CDAW Purge/Delete Options 32
III.C.2 . VMS Subdirectories 33
III.C.3 . CDAW Save and Restore Options 34
III.D. An Introduction to "Filters" 36
III.E. "Dimensional Data Sets" and the CDAW Graphics System 41
III.F. Selection of "User Specified" Data Sets 49
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IV. GETTING STARTED: DATA MANIPULATION 51
IV.A. Options in Data Manipulation 52
IV.A.1. File and Variable CDAW-9 Naming Conventions. 55
IV.B. LIST/SUBSET/TIME WINDOW (Full Screen Interface) 56
IV.C. More About TAE, with CDF / Data Set List as an Example 61
IV.C.1. Menu options: 61
IV.C.2. Tutor Options: 63
IV.D. How to Access and Work with CDF Data in IDL. 65
V. A "HODGEPODGE" OF "INTERESTING" GRAPHICS FEATURES 115
V.A. A Definition of the "Select" Menu Options: 115
V.B. Details with Respect to XY and Panel Plots 117
V.B.1. Specify Multiple X-Axes: 117
V.B.2. Specify an "animation" parameter: 117
V.B.3. Specify a pseudo-color parameter (XY plots only): 118
V.B.4. Sort / Change data representation values / Set Fonts: 118
V.C. Histograms 119
V.D. An Introduction to Handling Imaging Data 119
V.E. Map Projections Available under the CDAW Software. 122
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LIST OF FIGURES
Figure II.1. The "Root" or "Initialization" Menu 4
Figure II.2. A Sample DMS Screen 7
Figure II.3. DMS Screen After Editing and Immediately Before Linking to
the Selected Data Sets 10
Figure II.4. The (Graphics) "Select" Menu 11
Figure II.5. A Sample XY Plot: ISEE-1 Magnetic Field (GSM) Components
During Event 9B 12
Figure II.6. A Sample Panel Plot: ISEE-1 Magnetic Field (GSM)
Components During Event 9B 13
Figure II.7. CDAW Summary Screen / Initial Control Page. 14
Figure II.8. CDAW Summary Screen / Final Control Page. 18
Figure II.9. CDAW Summary Screen / Initial Specification Page. 18
Figure II.10. Specification Page with Variable Select Pop-up 22
Figure II.11. CDAW Summary Screen / Final Specification Page. 24
Figure II.12. CDAW Summary Screen / With Action Menu. 24
Figure III.1 . ISEE-1 and IMP-8 Magnetic Fields 29
Figure III.2. TAE "Tutor" for Post-Processor File Name Specification 30
Figure III.3. IMP-8 B-Field Components and Variances. 37
Figure III.4. Specification Page with Global Filter Select. 38
Figure III.5. IMP-8 B-Field Component Values with BZ Variance <0.1 nT2. 39
Figure III.6. IMP-8 B-Field Components with VARZ <0.1 nT2 and BY GSE
Plotted Only Where BX GSE >3 nT. 40
Figure III.7. Variable Selection Pop-up for 2-Dimensional CDF 44
Figure III.8. SIMPLIFIED Filter Interface for 2-Dimensional CDF:
Automatic Prompt for Filter Definition on 1st Dimension. 44
Figure III.9. How Filters Set by the SIMPLIFIED Interface Look. 45
Figure III.10. CCE Hot Plasma: Flux at 3 Energies and 10 degree Pitch
Angle 46
Figure III.11. Event 9A CCE Hot Plasma Fluxes (all Energies / Pitch
Angles). 46
Figure III.12. Discrete Variable Value Select "Pop-up". 47
Figure III.13. CCE Hot Plasma Energy Spectra at 5 Pitch Angles 49
Figure III.14. Directory Path Specification Form on "Uselect". 50
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Figure IV.1. The "Datamanip" Menu. 52
Figure IV.2. Definition of Data Manipulation Options. 53
Figure IV.3. Initial LIST/SUBSET/TIME WINDOW Screen. 56
Figure IV.4. LSTW with CDF Selection Pop-up Menu 57
Figure IV.5. LSTW Summary Screen while Selecting Variables. 58
Figure IV.6. LSTW (Optional) Pop-up Prompt for Discrete Variables 59
Figure IV.7. LSTW PF1 "Action" Menu. 60
Figure IV.8. A Sample LIST Output to Terminal. 60
Figure IV.9. A Sample "Tutor" (CDFLIST in Data Manipulation) 63
Figure IV.10. A Sample "Tutor" (LIST under CDFLIST). 64
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I. GETTING STARTED: AN OVERVIEW
Key to attacking the problems of global magnetospheric structure and dynamics
that are foci of the CDAW-9 analysis is the use of many simultaneous
measurements from different locations/observing platforms and different
instruments. CDAW-9 is focused on data from the PROMIS (Polar Regions Outer
Magnetosphere International Study) observational campaign period March-June
1986. This has greatly enhanced the number of time periods with simultaneous
observations and the number of observations taken, with the result (we hope) of
opening some very new and exciting science results to the CDAW-9 effort.
A distinguishing feature of the CDAW approach is the assembly of the relevant
data as a digital data base, with all the data contributed to the workshop cast
into a common format and software available to then access and aid in the
analysis of the resulting data base. The data base is most easily envisioned
as organized in a hierarchy. The keys to this data base are, then
o EVENT (namely Events 9A through 9E)
o SPACECRAFT (or Observing Platform; e.g., DE-1, Viking, ISEE-1, IMP-8,
Ground-Based); and
o INSTRUMENT (or Data Set; e.g., Magnetic Field, Energetic Particles
0.1-2 MeV, Canadian Ground Stations, South Pole Riometer).
As a user, the graphics system (in particular) will prompt you with the data
sets currently available in exactly these terms and will allow you to easily
combine up to five such data sets in making plots.
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The access and analysis software system, also known as the Network- Assisted
Coordinated Science or NACS system, is organized as a "tree" through which one
moves to access various functions. In a highly simplified view, the functions
distribute/flow as:
Initialization > Data Manipulation > Listing
Averaging
Math Functions
Subsetting
> Graphics > Specify Data Sets
> Specify plotting options
> Draw plot on terminal
> Make Graphics Hardcopy
(run after plots made on terminal)
A complete catalog of the contents of individual data sets is included within
the CDAW 9.2 Participant folders. Periodic updates to these catalogs will take
place as the remainder of data sets submitted can be ingested into the data
base or as new data submissions take place.
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II. GETTING STARTED: A SIMPLE GRAPHICS EXAMPLE
The current contents of the CDAW-9 data base are summarized in the preceding
table, which includes the time periods (or "Events") now defined for the CDAW-9
analysis, the specific platforms (e.g., "Spacecraft"), and the data sets (or
"Instruments") currently available in the data base.
From the table and catalog, we will suppose that you have decided you would
like to examine ISEE-1 magnetic field data and compare it to IMP-8 magnetic
field data for Event 9B.
Event 9B can be seen in the summary as defined to cover the period
April 2, 1986 / 1800 UT through April 3, 1986 / 1000 UT.
The software system will prompt you for information as needed to select this
data from the data base and graph the data, so we can begin immediately without
the need for further written notes here.
II.A Invoking the CDAW Software
II.1) At the VMS "$" prompt, type "cdaw" and a carriage return.
"cdaw" may be typed as either lower or upper case; you do not type the
quotation marks.
A carriage return will henceforth be abbreviated [CR].
You will now see a brief introductory page to the CDAW/NACS software. The
introductory page includes the date of the system release with which you are
now working and whether it is an "operational" or "development" version.
II.2) Enter [CR] when prompted to do so.
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You will now be prompted as to the VMS system priority at which you wish to
run. Normal VMS interactive priority is "4". During CDAW meetings, you will
have the option to specify a priority "5". For the benefit of your fellow
participants and other users of the NSSDC computers, we suggest you specify
"no change" when the system response seems generally adequate but use "5" when
necessary to accomplish your work.
II.3a) Enter "5" and [CR]; or only [CR]
You may now be prompted as to the kind of graphics terminal on which you are
working. If you do not receive this prompt, we have preset the appropriate
terminal type, and you should skip over step #3b.
Valid terminal type abbreviations may be found by typing "Help" and [CR]. For
the CDAW 9.2 workshop, you will be typically working on Tektronix 4100 series
terminal emulator software.
II.3b) (If prompted), please enter "T4100" or your true terminal type and
[CR]
The software now goes through an initialization stage, with messages
that refer to use of the Transportable Application Executive (TAE)
(currently at version 2.2A). When that initialization is completed, you
will see a display of options (a TAE "menu") as shown in Figure II.1.
Figure II.1. The "Root" or "Initialization" Menu
____________________________________________________
Menu: "ROOT", library "nacs$menu"
NACS System Development Vers. - Subsystems Menu
1) DATA MANIPULATION [ DATAMANIP ]
2) GRAPHICS [ GRAPHICS ]
3) FILEDEL Delete all working files and continue [ NACSDEL ]
4) EXITPUR Purge all working files and exit to $ prompt [ EXITPUR ]
5) EXITDEL Delete all working files and exit to $ prompt [ EXITDEL ]
Enter: selection number, HELP, BACK, TOP, MENU, COMMAND, or LOGOFF.
?
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Additional options are available under TAE as you will note on the "command"
line at the bottom of the menu (e.g., back, top, etc.), but you should ignore
these options for now.
II.5) For the purpose of this introductory tutorial , please enter "2"
(graphics) and [CR]. Remember, you don't type the quotation marks, just the
number.
You will now be presented with another TAE menu, offering the options of the
o Graph Utility Menu, or the
o Run Graphics Post-Processor
II.6) Enter "1" (Graph Utilities) and [CR].
You will presented with a 3rd TAE menu (be patient: it gets more
interesting after this step), presenting you with the choices:
o Manual CDF Data File Selection
o CDAW8 Window CDF Data File Selection
o CDAW9 Window CDF Data File Selection, or
o Restore Named Total Graphics Environment
We'll explain the "manual selection" and "restore" options later.
For now, please:
II.7) Enter "3" (CDAW-9 Data Selection Summary) and [CR].
You will now see several system messages as system logicals are redefined,
followed by display of the Data Management Summary (DMS) screen.
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II.B Data Management Selection/Summary Screen:
The Data Management Summary or DMS screen is a full screen alphanumeric display
structured to allow the easy identification and selection of desired data sets
from within the CDAW-9 data base. The forms will display best on a graphics
terminal with full ANSI-standard (VT100 or VT100-compatible, effectively)
alphanumeric display.
This summary form is possible (as noted before) because the CDAW-9 data sets
are typically well-organized by the three essentially orthogonal specifications
of:
o Event (or Time Period)
o Observation Platform (Spacecraft name or catagories such as
Ground-Based observations, Model Data), and
o Instrument or Data Set
Where data sets in the central data base are not uniquely identified by this
organization (e.g., a data set with data from more than one event), the same
data set is filed under multiple specifications. Access to data not in the
central data base is also provided but will be discussed in a subsequent
section. Up to 5 distinct data sets may be selected at one time.
When the DMS screen is first invoked, the user is prompted to specify first the
event/time period of interest, then a platform/spacecraft, then a specific
instrument or data set. The DMS interface allows only valid selections at each
step. The screen consists of 5 sections as illustrated in Figure II.2.:
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o Selected Data Sets Form
(Shows current selections made)
o Option Select "Pop-up" Menu
(Shows the valid choices for selections at this step)
o Help Text Display ("pops-up" if requested via PF4)
(Shows additional text description for given selection)
Figure II.2. A Sample DMS Screen
[** Figure II.2 is deleted from this text-only version. **]
o Keypad Definitions Box
(Shows valid keystrokes and meaning at current time)
o Message Buffer
(To hold additional instructions or system messages)
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To recall, we are looking for:
ISEE-1 and IMP-8 magnetometer data, for event 9B.
To select these data sets, we proceed as follows:
II.8) Use the "down-arrow" key to move the highlight field past "User_select"
down to the field:
"Evnt 9B 2Apr86/1800 - 3Apr86/1000UT",
in the Option Select "pop-up" menu where the events that can be selected are
listed. If you wish in these kinds of pop-ups, you may use
- the "down-arrow" to scroll down the list of events
- the PF3 key to page down the list of events
- the "up-arrow" to scroll up the list of events
- the PF2 key to page up the list of events.
Valid keys are shown in the Keypad Definitions box.
Should you happen to accidentally press PF1 at any point, highlight "Continue"
and press PF1 again to continue editing.
Also note that "control-w" will redraw the screen. This might be necessary if
you should encounter noise on the line between the computer and your terminal
or if the display is modified by e.g. an incoming mail or operator message
while the screen is being drawn. "cntl-w" has no other effect.
II.9) Use the PF4 key to display a brief help text on this event. You must
then use that same PF4 key to remove the help text window.
II.10) [CR] is used to select an entry from the "pop-up". Press [CR] while
"Evnt 9B" is highlighted to select event 9B.
When you have selected an event, that selection is entered into the Selected
Data Sets form at the top of the screen and the selection cursor / selection
options menu are moved to the next field for selection, in this case
"SPACECRAFT" (or observing platform). Valid spacecraft / platform selections
are now shown.
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If you had accidentally selected another "event", you could use "control-h" to
move back on the Selected Data Sets form to the event field and Option Select
pop-up for events, so that you could change your selection to event 9B.
II.11) Use the "down-arrow" and PF3 keys to highlight "ISEE-1". You may
again wish to use PF4 to look at a brief descriptive summary of the
ISEE-1 spacecraft.
II.12) Press [CR] while "ISEE-1" is highlighted to select that spacecraft.
You will now see a display of Instruments / data sets currently in
the CDAW-9 data base for ISEE-1. Again, "control-h" allows you to
backspace and correct any errors made in the spacecraft selection.
II.13) If more than one data set were available for ISEE-1, you could use the
arrow keys and / or PF2 / PF3 to move the highlight to the magnetometer
data set (data set mnemonic I104). Note that the magnetometer data is
loaded at 4-second resolution.
II.14) Use [CR] to select the magnetometer data.
At this point, you'll notice that the system has positioned you to
define another set of event / spacecraft / instrument specifications.
You can select any number of data sets from one to five. In this
example, we actually select only two data sets. But if you really only
wanted to see the magnetometer data, you could simply skip the next
step.
II.15) As above, select "Event 9B" and "IMP-8".
The first IMP-8 data set displayed on the selection menu is magnetic
field. By calling "help" for that data set (using PF4), we can also
see that spacecraft position data has been included in this data set.
II.16) Use [CR] to select the IMP-8 magnetic field data set.
You are now positioned to specify a third, fourth or even a fifth data
set. But we're in fact ready to move on for the purposes of this
example.
Therefore, as prompted in the "Keypad Definitions" box,
II.17) Press PF1 to display the "action" options for the DMS screen. The
result is the screen display shown below in Figure II.3.
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Figure II.3. DMS Screen After Editing and Immediately Before
Linking to the Selected Data Sets
[** Figure II.3 is deleted from this text-only version. **]
PF1 gives access to three options, namely:
o Link to (or "load") the selected data sets (passes control to graphics)
o Select a data set not in the primary CDAW-9 data base
o Exit the DMS screen
(without saving or linking to the selected data sets)
Load is the default and is highlighted.
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II.18) Press [CR] to link to the selected data sets.
Several messages will now be displayed as the software system links to the
specified data sets (stored in the CDAW-9 data base in a form known as the
Common Data Format or CDF). When complete, a prompt will appear to "enter
return".
II.19) Enter [CR].
At this point, another TAE menu (the "select" menu, as noted on the upper left
hand corner of the screen) offers some 16 distinct choices in the kinds of
graphics that are possible.
Figure II.4. The (Graphics) "Select" Menu
__________________________________________________
Menu: "SELECT", library "nacs$menu"
Plot Type Selection Menu (NACS)
1) Histogram Menu [HIST2]
2) X-Y Plot Menu [XY]
3) Panel Plot Menu [PANEL]
4) Mapped X-Y Plot Menu [XYMAP]
5) Contour Plot Menu [CONTOUR]
6) Mapped Contour Plot Menu [MAPCONT]
7) Pseudo-Color Image Menu [IMAGE]
8) Mapped Image Plot Menu [MAPIMAG]
9) Surface Diagram Menu [SURFACE]
10) Mapped Surface Plot Menu [MAPSURF]
11) MERLIN Plot Menu [MERLIN]
12) CDAW Summary Screen (CDAWSUM)
13) Save/Restore/Delete XY & Panel Environment (.PAR files) [SAVEREST]
14) Save/Restore/Delete Graphics Environment (All files) [TOTSAVRES]
15) Purge all working files and exit to $ prompt (EXITPUR)
16) Delete all working files and exit to $ prompt (EXITDEL)
Enter: selection number, HELP, BACK, TOP, MENU, COMMAND, or LOGOFF.
?_________________________________________________
That there are so many choices reflects the range of graphics applications to
which the underlying CDAW software can be bent. As you become more familiar
with the system and its capabilities, you may have occasion to explore these
options more fully (they are described at least in summary in subsequent
sections).
But for now, our thrust is towards "simple" graphics and the summary interface
which has built in the CDAW system to support access to those graphics.
II.20) Therefore enter "12" (CDAW Summary Screen) and [CR].
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II.C CDAW (XY/Panel Graphics) Summary Screens:
At this point, we are ready to begin plotting data.
XY and Panel plots are both "line" (Y versus X) plots. In an XY plot in the
CDAW system, all curves plotted (to a limit of 5 Y variables versus a single X
variable, as presented in the Summary screen interface) are overlaid on a
single grid or panel. Separate scales for each Y variable are displayed.
Figure II.5. A Sample XY Plot: ISEE-1 Magnetic Field (GSM)
Components During Event 9B
[** Figure II.5 is deleted from this text-only version. **]
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In a Panel plot, up to 6 curves of Y variables versus a single given X variable
may be defined on 3 separate grids or "panels", with up to 2 curves per panel
and with separate scales shown for each Y variable.
Figure II.6. A Sample Panel Plot: ISEE-1 Magnetic Field (GSM)
Components During Event 9B
[** Figure II.6 is deleted from this text-only version. **]
For simplicity, the first plots we'll define will be to show three components
of magnetic field for ISEE-1 and IMP-8:
o For ISEE-1, overlaid on a single grid (XY plot; i.e. Fig II.5)
o For ISEE-1, plotted on 3 separate grids (Panel plot; i.e. Fig II.6)
o For ISEE-1 and IMP-8 together on a Panel plot.
The last two plots will actually be completed in section III; the thrust of
section II is to get you from starting the system through your first plot.
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The (XY/Panel Graphics) Summary Screens consist of two full-screen "forms" or
"pages", set such that one is always "behind" (i.e., covered up by) the other.
The PF2 key is used to toggle between the two pages.
The first (or "control") page is concerned with specifying some general
plotting options (e.g., XY or Panel plot, plot separate or joined points,
automatic scaling to the actual Y variable ranges or manual scale
specification, a user name to appear on the plots, etc.).
The second (or "specification") page allows definition of the variables to be
plotted, the plot scale limits and kinds of axes and "filters", which will be
explained in more detail in section III.
Depending on the option set, the PF1 key is used variously to save plot options
and execute the graph, save the plot options and exit the Summary screen, or to
exit the Summary screen without saving new changes.
Figure II.7. CDAW Summary Screen / Initial Control Page.
[** Figure II.7 is deleted from this text-only version. **]
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II.C.1 Graphics Summary Screen - Control Page
On entering the XY/Panel Graphics Summary screens, the cursor is positioned
on the 1st or control page and is positioned to allow the definition of plot
type (XY or Panel), with default selection of Panel.
II.21) In general, all plotting parameters where only specific choices are
possible are selected via a "pop-up" menu invoked by PF3. While positioned on
the "Plot type" field, PF3 thus brings up a selection box showing the XY and
Panel options. The user should use up-arrow and down-arrow keys to move the
highlight to the desired selection (XY here), then [CR] to make that selection
and move to the next field.
II.22) The cursor is now positioned to specify the"Plot style". If an error
had been made in setting the plot type, "control-H" could be used to backspace
and PF3 to re-select the plot type as before.
Plot style options (displayed using PF3 again) include:
o SCATTER Plot symbols and error bars for each point
o VECTOR Join successive points with straight lines
o SPLINE XY option only, spline fit to data
o SCATTER/VECTOR XY option only, combined styles
o SCATTER/SPLINE XY option only, combined styles
II.23) Since a vector plot is appropriate, use the "down-arrow" key to
position to the VECTOR option, then [CR] to select that plot style.
In the terminology of this system, "Scaling" is the definition of minimum and
maximum plot limits. Options for scaling (mode) are:
o MANUAL Default to preset plot limits (defined by NSSDC when
building the CDAW-9 data base), with the user then
having the option to manually reset those limits
o AUTO (Panel option only) The data to be plotted are
pre-processed to determine true range, with minimum /
maximum values then derived with respect to these.
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II.24) For this initial XY plot, MANUAL is the only option valid. Enter [CR].
You will then be successively prompted for 3 name / title fields:
o User
o Plotfile
o Plot title
User (name) and Plot title will appear as fields on the graph you produce,
Plot file (name) is the name under which you will (optionally) save these plots
for later review or to print.
II.25) For User, enter your own name (abbreviated to <12 characters) and
[CR].
II.26) For Plot file, enter a name like "demo_plot" (no spaces and <29
characters) and [CR]. If a plot file of that name (which will appear to a
"$ dir" VMS command under the name of "demo_plot.plt") already exists, any new
plots will be appended to the existing file.
WE STRONGLY RECOMMEND YOU ALWAYS SPECIFY A PLOT FILE NAME, IN CASE YOU SHOULD
DECIDE TO LATER TO SAVE A PLOT; the system will not allow a plot to be saved
unless a Plot file name has been specified.
II.27) For Plot title, you might choose to enter a title (<39 characters and
followed by [CR] ) like
"Demo - ISEE-1/IMP-8 Magnetic Field Comps"
The 1st screen or control page should now look like figure II.8.
II.28) The next specification is that of "Font". Two options can be selected
using PF3 and [CR], namely:
o FAST / HARDWARE characters Uses graphics characters defined by default
for your terminal. The plot will generally
be faster than using SLOW characters, but
the quality will be lower.
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o LOW / SOFTWARE characters Graphics program draws all text characters on
the plot. Quality is better than fast, but
drawing speed (particularly on a low speed
link) is a problem.
We'll assume we have an adequate speed link to use software characters, so type
PF3, down-arrow and [CR] to select LOW / SOFTWARE.
II.29) The use of the term "filtering" in this system will be discussed later.
The "Filter Interface" relates to how the 2nd (specification) summary screen
page prompts the user for information on "filters" when they are (usually)
needed. The two interface options are:
o NORMAL Allows full access to system capabilities to construct
complex X-Y graphics, but with some risk that an
inexperienced user may not enter all required information to
generate a sensible plot.
o SIMPLIFIED Interface for more novice users, which prompts for all
information usually required to define a sensible plot.
The default is the SIMPLIFIED interface. Use [CR] to accept the
default.
II.30) PF1 should generally be entered only after filling out the 2nd screen
or "Specification" page. The user should note that it can be invoked however
at any time to save editing done to that time or to quit the Summary screen
without saving any of the last changes.
Now press PF2 to toggle to the 2nd screen .
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Figure II.8. CDAW Summary Screen / Final Control Page.
[** Figure II.8 is deleted from this text-only version. **]
Figure II.9. CDAW Summary Screen / Initial Specification Page.
[** Figure II.9 is deleted from this text-only version. **]
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II.C.2 Graphics Summary Screen - Specification Page
The specification page allows definition of the variables to be plotted along
the X-axis and Y-axis (up to 5 curves for an XY plot or up to 6 curves grouped
by twos onto three PANEL plots). Only a single X-axis variable may be defined
for a plot from the Summary screen (use of the TAE interface for XY plots
allows separate X-axis variables to be set for each of the up to 5 curves on an
XY plot).
For the X-axis variable and for the individual Y-axis variables, the user can
set:
- choice of (data set) variable
- minimum range of the plot
- maximum range of the plot
- choice of linear or logarithmic scales
- specification of "global" and/or "per-curve" filters (to be defined later)
We will try to consistently use the terms:
o Variable Named input data quantity
(e.g., X-component of B in GSM coordinates)
o Curve Individual "Y-axis variable vs X-axis variable" line or trace
on the final plot
o Parameter One of the options associated with each curve
(e.g., name of the variable or min/max scale limit)
On first display of the specification page, the cursor is positioned to the X-
axis variable specification field. For the convenience of CDAW users, the X-
axis defaults to "TIME", although it can be reset to be any variable from the
loaded data sets.
For purposes of key definitions, there are two primary states of the
specification page: (1) no "pop-up" selection menu displayed (e.g., Figure
II.9) and a "pop-up" menu displayed (e.g., Figure II.10).
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Key definitions with no pop-up menu displayed generally include:
[CR] move one field right, wrapping at end of line to next line
cntl-H move one field left, wrapping at start of line to last line
up-arrow move one field up
down-arrow move one field down
left-arrow move one character right (on entering min/max)
right-arrow move one character left (on entering min/max)
PF1 draw plot and/or exit/quit Summary Screen
PF2 toggle to 1st (control) page
PF3 display "pop-up" selection menu for field (if applicable)
"delete" null selection of variable on line where cursor is currently
located (if applicable)
cntl-W redraw the screen (no change to options selected)
Key definitions with pop-up menu displayed generally include:
up-arrow move highlight one selection up
down-arrow move highlight one selection down
u page highlight up
d page highlight down
[CR] select highlighted value & move one field right
cntl-H no change in selected value & move one field left
II.31) Press [CR] to accept "TIME" as the X-axis variable of the plot.
Because we have selected MANUAL scaling, we are now positioned successively to
the X-axis parameter fields from which we can specify minimum and maximum range
of TIME values to be plotted.
At present, times are encoded as an integer of the form:
YYYYMMDDHHMMSS YYYY = Year
MM = Month (1-12)
DD = Day of month (1-31)
HH = Hour of day (0-23)
MM = Minute of hour (0-59)
SS = Seconds of minute (0-59)
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A prompt in the message buffer at the bottom of the screen serves as a reminder
to this encoding. The minimum and maximum scales for Time default to the event
limits in most cases. Because this is only 4-second resolution data, we will
adjust the time boundaries to run between 00 and 02 UT on April 3rd.
II.32) Use the left-right arrow keys and keyboard to modify the time
minimum from
19860402180000 to 19860403000000
[= 1986 April 2 / 1800 UT] [=1986 April 3 / 0000 UT]
then enter [CR] , then modify the time maximum (followed by [CR] )
from
19860403100000 to 19860403020000
[= 1986 April 3 / 1000 UT] [=1986 April 3 / 0200 UT]
Variables may be plotted on linear ( LIN ) or logarithmic ( LOG )
scales (switch using left-right arrow keys), but TIME is clearly
most meaningful in the (default) linear scale.
II.33) Enter [CR] to accept the default linear X-axis scaling.
II.34) With the SIMPLIFIED "Filter Interface", the "Filter?" field should
generally be ignored. We will discuss the meaning and use of the "Filter?"
field in a subsequent section. For now, enter [CR] to accept the default "N"
(No Filters).
II.35) You are now ready to specify the Y-axis parameters, starting with the
Y-variable to be plotted on the first curve. Press PF3 to bring up a "pop-up"
menu of valid variable names (from the earlier-linked / loaded data sets) for
selection (see Figure II.10). As noted above, you may use the up-down arrow
keys to scroll the variable selection menu, and the keys "u" and "d" to page up
and down on that menu.
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Figure II.10. Specification Page with Variable Select Pop-up
[** Figure II.10 is deleted from this text-only version. **]
When the variable name you desire is highlighted, use [CR] to actually select
that variable for plotting (as one of the "curves" Y#1 through Y#5) and
(simultaneously) move right to edit the minimum plot range value.
II.35) The first variable we desire to plot happens to be the initial value in
the pop-up variable selection menu.
I104BSMX T BX GSM
Had it not been, one would use the up-down arrows and u-d keys to position the
highlight to the desired variable. The variable mnemonic I104BSMX indicates /
reminds that this is ISEE-1data (from the first two characters "I1"); the
longer variable name confirms that it is the BX field component in GSM
coordinates. The column of "T"s should be ignored for now (they relate to the
"dimensional variance" of this variable in this CDF). The detailed CDAW-9
catalog listing can also be consulted to confirm the identification and find
the units for this variable (nT).
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NOTE: if you have selected a data set with "dimensionality" >0, you may see
additional prompts to specify constraints after selecting some variables.
These prompts are discussed in Section III.E but are intended to function
transparently under the SIMPLIFIED Filter Interface.
II.36) Use [CR] to select the highlighted I104BSMX as the variable to be
plotted (versus time) as curve Y#1. The cursor is positioned to enter the
minimum range of I104BSMX to be plotted.
At this point, you may either edit the minimum (and then maximum) ranges for
curve Y#1 or define the variables for curves Y#2 and Y#3.
Note that selecting a new variable for a given curve replaces the current
values of the minimum / maximum range for that curve, so you must always select
the variable before attempting to edit. Aside from this caveat, the order of
entering values is at the user's discretion.
II.37a) TO EDIT MINIMUM / MAXIMUM: The desired range is -30.00 to 30.00 nT.
Editing is "overtype" mode, not "insert" mode. Left-arrow and right-arrow keys
are used to position to characters in the field to be overtyped. [CR] is used
to enter the edited value and move to the next field. cntl-H may be used to
backspace among fields; e.g. to correct errors.
II.37b) TO SELECT VARIABLES FOR ADDITIONAL CURVES: Use the down- arrow key and
cntl-H to position to the "Variables" field for curve Y#2. Then enter PF3 to
bring up the pop-up selection menu, down- arrow to move the highlight to
I104BSMY and [CR] to select that value. And so on.
Note again that the "delete" key (the VT100 delete, wherever your specific
terminal or emulator may have placed it) is used to "null" the selection of a
variable for a given curve.
II.37c) TO EDIT LIN / LOG: Although in this case, we intend to accept the
default linear scaling, that scaling could be changed for a given curve by
positioning to the appropriate field, then using PF3, up-down arrow key and
[CR] to alter the selection as desired.
II.37d) TO CHANGE FILTERS: For this introduction and with the SIMPLIFIED
interface set, please ignore this option.
II.38) In whatever order desired, select the variables I104BSMX, I104BSMY,
I104BSMZ and define min / max limits -30 to +30 nT, with linear scaling.
At this point, the Specification page should look like Figure II.11.
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Figure II.11. CDAW Summary Screen / Final Specification Page.
[** Figure II.11 is deleted from this text-only version. **]
Figure II.12. CDAW Summary Screen / With Action Menu.
[** Figure II.12 is deleted from this text-only version. **]
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II.39) To bring up a menu from which you can draw the plot, press PF1. The
resulting screen is shown in Figure II.12, where the "action" selection pop-up
menu has appeared.
The four "action" options currently allowed are:
o DRAW / SAVE Save new plot settings and draw the specified plot
o EXIT / SAVE Save new plot settings but exit without drawing the
specified plot
o QUIT / NOSAVE Discard any specification changes made since the last save
and exit without drawing the plot .
o CONTINUE Return to Summary screen and continue editing
The default action is "draw / save" which is selected and executed by [CR]. To
choose another option, move the highlight with the up- down arrow keys.
II.D And Here Comes the Plot!
You will now see the summary screen form erased and the message "Summary file
clean-up taking place" displayed. After a few moments, you should see the
terminal screen automatically switched from the alpha-numeric to graphics
display, and the plot being drawn.
Some terminals or terminal emulators, sometimes depending on their detailed
setup, may require you to manually toggle "ON" the graphics display or to
toggle "OFF" the alphanumeric display (or dialogue "box"). The terminal should
"beep" when the plot is completed.
[A plot may generally be interrupted/aborted by hitting a few successive
"control-C" 's. If you need to interrupt the plot, you should then toggle the
alphanumeric display "ON" (possibly a sequence like "control-C, toggle,
control-C, toggle") until you see the message "NACS-INTERRUPT>" displayed. At
this point, type "abort" and [CR] , then [CR] when prompted again to return to
the TAE plot selection menu.]
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II.D.1. Now that you have a plot displayed:
The plot you now see displayed on your terminal should generally match that
shown earlier (Figure II.5) as what we were aiming for; namely a plot within
Event 9B (3 April 1986 / 0000 UT to 3 April 1986 / 0200 UT) of the 3 GSM
components of the magnetic field measured at ISEE-1. These are overlaid on
a single grid but with multiple scales.
Note the various labels on the plot, including user name, plot title,
date/time, the VMS file specification of the data sets currently being used,
the variable labels and variable mnemonics with the plotting symbols shown.
For XY and Panel plots, a frame is displayed around the plot, at the bottom
of which are reminders of what keys / actions can be taken. Not all are
relevant for this simple plotting example. The relevant commands are:
o s Save a "snapshot" (digital binary copy of the plot displayed) into a
file with the "plot file" name you specified on the control page
(demo_plot in this example, which will then refer to a VMS file named
"demo_plot.plt" that will be created or appended to in your
directory)
o q Quit this plot and return to the plot selection menu
o h Make a hardcopy of the plot directly (if you are working on a
graphics terminal with a directly attached hardcopy device).
To continue/complete this simple example:
II.42) Press "s" (DO NOT PRESS [CR] HERE!!).
When the terminal "beeps", you may then press "q" and [CR] when prompted.
As above, depending on the terminal, you may need to manually toggle the
alpha-numeric (dialogue) display to see the prompt to enter [CR].
You have now been returned to the Graphics Selection (TAE) menu (the one with
16 choices!).
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II.D.2. To re-enter the XY/Panel Summary screens:
II.43a) Enter "12" and [CR].
II.D.3. If you wish to interrupt this tutorial at this point:
II.43b1) Enter "15" (purge files and exit to $ prompt, instead of "12") and
[CR].
NOTE THAT "PURGE" WILL ESSENTIALLY NEVER REMOVE ANY FILES ACTUALLY USEFUL TO
YOU (UNLESS YOU BECOME VERY SOPHISTICATED IN THIS SYSTEM). "Purge" will help
to keep your disk directory cleaned-up and so it should be used.
"Delete" should only be used if you have no interest in returning to this plots
or are willing to re-specify all the setting and selections made above.
At this point, you have been returned to the VMS operating system (the $ prompt
level) and may look at mail, logoff your account for now, etc.
II.D.4. When you wish to resume this tutorial:
II.43b2) Type "cdaw" at the $ prompt and execute instructions #2-4 from
above. Instead of executing instruction #5 however (select option #3
for graphics):
II.43b3) Type "m select" and [CR].
You will be returned to the 16-choice "Select" menu with all options left set
(assuming you've not executed "cdaw" again outside these instructions), and you
can now go back to instruction II.43a above and continue.
END OF SECTION I (VAX version made 12/29/93)
(SECTION II will be prepared later, and will start with page 28.)
____________________________________________________________________________
Curator: H. Kent Hills (hills@nssdca.gsfc.nasa.gov)
Author and NASA Official: Robert E. McGuire (mcguire@nssdca.gsfc.nasa.gov)
Head, Space Physics Data Facility (Code 632), NASA/GSFC, Greenbelt, MD 20771
Last Revised: 22 Nov 1996 [HKH]
____________________________________________________________________________