MD Files - Listing MD file directories and Data Records

8.1 MD Files - Listing MD file directories and Data Records

In this exercise, you will list an MD file directory and information about its schema, and examine individual records in the MD file.

Start a McIDAS session.

At the Unix prompt:

Type: mcidas

Your session should still be set for six frames from the last time you edited your .mcidasrc file. If not, set it for six frames, as described in Getting Started.
Log on and initialize the workstation.

Type: LOGON initials project# I

List the point datasets available in the BLIZZARD dataset.

Type: DSINFO POINT BLIZZARD

DSINFO POINT BLIZZARD
        Dataset Names of Type: POINT in Group: BLIZZARD
Name         NumPos   Content
------------ ------   --------------------------------------
OBS              5    STORM OF THE CENTURY OBSERVATIONAL DATA
PTSRCS           5    STORM OF THE CENTURY POINT SOURCE OBS  
SFCHOURLY        1    STORM OF THE CENTURY SFC OBS
SHIPBUOY         1    STORM OF THE CENTURY SHIP/BUOY OBS
SYNOPTIC         1    STORM OF THE CENTURY SYNOPTIC OBS
UPPERMAND        1    STORM OF THE CENTURY UPPER MAND
UPPERSIG         1    STORM OF THE CENTURY UPPER SIGS
DSINFO -- done

List the file directories for the BLIZZARD/PTSRCS dataset.

Type: PTLIST BLIZZARD/PTSRCS FORM=FILE ALL

The dataset position number, schema type, number of rows and columns, and description for each MD file are listed.

PTLIST BLIZZARD/PTSRCS FORM=FILE ALL
Pos      Description                        Schema  NRows NCols 
------   --------------------------------   ------  ----- -----
     1   SURFACE HOURLY OBSERVATIONS        ISFC       72  3500  
     2   INTL. RADIOSONDE OBS (UPPER AIR    IRAB        8  1500 
     3   INTL. RADIOSONDE OBS--SIG LEVELS   IRSG       16  8000
     4   SHIP/BUOY OBSERVATIONS             ISHP       24  3000      
     5   SURFACE SYNOPTICS                  SYN         8  6000     
PTLIST: Done

List all the MD files stored on your workstation.

Type: DMAP MDXX

List the structure and keys in the ISFC schema.

Type: LSCHE ISFC

The keys, units, and scale factors for the ISFC schema are displayed as shown below. If the schema type does not exist, register the schema with the SCHE DCISFC command, and then try the LSCHE command again. See the introduction in the Unidata McIDAS User's Guide for more information.

LSCHE ISFC                                                                  
NAME: ISFC  VERSION:  7  DATE: 1999085  TEXTID: "SURFACE HOURLY OBSERVATIONS
----        -------                                                        
   DEFAULT NUMBER OF ROWS:   72                        INTEGER ID: 0      
                     COLS: 3500                   MISSING DATA VALUE:  -2139062144
   REPEAT GROUP:  NUMBER OF REPETITIONS:   1 
                      STARTING POSITION:  11
                                   SIZE:  25       
   NUMBER OF KEYS IN ROW HEADER:     4            
                     COL HEADER:     6   STARTING AT POSITION   5        
                    DATA RECORD:    25   STARTING AT POSITION  11       
                                  ----                                 
                                    35 TOTAL                          
                                                                     
        KEY  SCALE UNIT     KEY  SCALE UNIT     KEY  SCALE UNIT     
        ---- ----- ----     ---- ----- ----     ---- ----- ----    
        TYPE   0            DAY    0   CYD      TIME   0   HMS    
        NREC   0            ID     0   CHAR     LAT    4   DEG   
        LON    4   DEG      ZS     0   M        ST     0   CHAR 
        CO     0   CHAR     MOD    0            HMS    0   HMS 
        CIGC   0            CC1    0            CC2    0      
        CIGH  -2   FT       ZCL1  -2   FT       ZCL2  -2   FT
        VIS    1   MI       WX1    0   CHAR     WX2    0   CHAR             
        T      2   K        TD     2   K        DIR    0   DEG             
        SPD    1   MPS      GUS    1   MPS      PSL    2   MB             
        PCP    2   IN       SNO    0   IN       PRE    2   MB            
        P24    2   IN       WXC1   0   CODE     WXC2   0   CODE         
        WXC3   0   CODE     WXC4   0   CODE                    
LSCHE: DONE

List the parameters in the first file of the BLIZZARD/SFCHOURLY dataset.

Type: PTLIST BLIZZARD/SFCHOURLY.1 FORM=PARAM

Also listed are the units, storage type and format for each parameter.

PTLIST BLIZZARD/SFCHOURLY.1 FORM=PARAM                    
   PARAMETER UNIT        STORAGE TYPE     DEFAULT FORMAT 
   --------- ----        ------------     --------------
   TYPE                  integer          I9           
   DAY       SYD         integer          I9           
   TIME      HMS         integer          I9           
   NREC                  integer          I9           
   ID                    character        A4           
   LAT       DEG         real             F9.4         
   LON       DEG         real             F9.4         
   ZS        M           integer          I9           
   ST                    character        A4           
   CO                    character        A4           
   MOD                   integer          I9           
   HMS       HMS         integer          I9           
   CIGC                  integer          I9           
   CC1                   integer          I9           
   CC2                   integer          I9           
   CIGH      FT          real             F9           
   ZCL1      FT          real             F9          
   ZCL2      FT          real             F9           
   VIS       MI          real             F9.1         
   WX1                   character        A4           
   WX2                   character        A4           
   T         K           real             F9.2         
   TD        K           real             F9.2         
   DIR       DEG         integer          I9           
   SPD       MPS         real             F9.1         
   GUS       MPS         real             F9.1         
   PSL       MB          real             F9.2         
   PCP       IN          real             F9.2         
   SNO       IN          integer          I9           
   PRE       MB          real             F9.2         
PTLIST: Done

List the first record in the first file of the dataset.

Type: PTLIST BLIZZARD/SFCHOURLY.1

PTLIST BLIZZARD/SFCHOURLY.1                            
Row :      1  Col :      2                             
TYPE        =         0             | DAY         =     93072 SYD         |    
TIME        =         0 HMS         | NREC        =      1924             |   
ID          =       OAR             | LAT         =   36.6833 DEG         |  
LON         =  121.7666 DEG         | ZS          =        41 M           | 
ST          =        CA             | CO          =        US             |
MOD         =         0             | HMS         =    235500 HMS         |    
CIGC        =         2             | CC1         =         2             |   
CC2         = _missing_             | CIGH        =    15000. FT          |  
ZCL1        =    20000. FT          | ZCL2        = _missing_             | 
VIS         =      25.0 MI          | WX1         = _missing_             |    
WX2         = _missing_             | T           =    289.27 K           |   
TD          =    284.83 K           | DIR         =       270 DEG         |  
SPD         =       6.2 MPS         | GUS         = _missing_             | 
PSL         =   1019.31 MB          | PCP         = _missing_             |
SNO         = _missing_             | PRE         = _missing_             |    
---------------------------------------------------------------------------   
Number of matches found = 1                                                  
PTLIST: Done