In Lesson 1, you learned how to
download, install, and use mp from the command prompt.
Lesson 2 will now introduce parsing metadata.
Parsing your record involves more than just typing a
command. As indicated earlier (parsing
metadata), parsing with mp is:
-
Error
Checking:
Fortunately, mp checks metadata so you don't have to,
saving you hours of review. The errors are identified as discrepancies
between the values/syntax of the record and the metadata content
standard (CSDGM).
Your job is to correct those errors.
-
Output
file generation:
Using mp will allow the
user to generate output that can be utilized for data
distribution. MP gives you the opportunity to
generate two web based file types, SGML, Text, and DIF output
types. Lesson 3 will examine these files and how best you
can use them..
Learning how to develop strategies that will allow you to
efficiently parse metadata is the primary goal for this lesson. Following
the steps below, you will be introduced to a sample metadata record
developed with specific syntax and positional errors. These errors
represent some of the most common mistakes encountered by parsing.
[Go To Step 1: Parse
your record]
Step
1: Parse the metadata record
There are a number of procedures that ensure successful parsing
of metadata. Organization is the best strategy you can employ. For
beginners, it's a good idea to focus on these 4 process steps:
-
Parse the metadata
record
-
Review the
errors
-
Correct the errors
-
Do it again...
Today's lesson may not be provide the most direct
strategy for parsing metadata, but it will provide the
novice user
with the knowledge and abilities needed to complete the task.
Naturally, you are encouraged to develop strategies that best work for
you.
(Command Prompt window used with mp)
This command generates the "error.txt"
file in the c:\temp
directory that contains all the errors in the file "jltreasure.met" detected by mp.
[RETURN TO TOP] [NEXT
STEP]
149 errors: 1 misplaced, 12
too_many, 135 missing, 1 bad_value
While the number of errors seems
alarming, it's quite normal, especially for beginners. Don't be discouraged.
Correcting these errors are usually as simple
as changing one value, as you will see...
[RETURN TO TOP]
[NEXT STEP]
-
Step
3: Correcting the errors
There are a number of different ways to
correct errors. Some individuals prefer to edit their metadata
record using Microsoft Notepad. Others use the application that
initially developed the metadata. Finally, some use a combination
of both Notepad and their development app.
Step 3
will use Corpsmet95 to correct any obvious methods. Later,
in Step 5, you will see how to correct errors using
Notepad.
Correcting errors using
Corpsmet95
- Open Corpsmet95
- Open the
"jltreasure.met" file located in
c:\temp:
(Corpsmet95 Open dialog box)
- Identify any obvious error as
indicated by the
icon and correct them. Take a close look at the errors:
(Corpsmet95 metadata project box)
- Familiarize yourself with the errors. Identify how and why they caused
problems. Some are more obvious than others.
- Making the corrections:
Reviewing the metadata record, you will need to make the
following corrections:
- Identification > Description > Abstract:
The digitized features identifying the potential locations for
the legendary treasure(s) of the pirate Jean Lafitte.
- Identification > Access Constraints:
Select "No Access Constraints"
- Identification > Point of Contact:
Select "Organization"
- Data Quality > Completeness Report:
Information regarding the Jean Lafitte treasure are purely
fictional and not based on substantive information.
- Spatial Reference > Horizontal Coordinate System
Definition > Planar 1 > Grid Coordinate System:
Select the tab titled "Universal Transverse
Mercator" and enter "0" for "False Northing"
- Data Distribution > Distribution Information 1 >
Distributor:
Select "Organization"
- Save the corrections:
Select "Project" from the Corpsmet95
menu and choose "Build metadata file." Make
sure you are in the c:\temp
directory. This will over-write the original
"jltreasure.met"
file you downloaded.
(Corpsmet95 Create Metadata File dialog box)
With the corrections made, it's time to parse the
metadata record again...
While these errors were obvious, it does demonstrate an
important features of Corpsmet95:
[RETURN TO TOP] [NEXT
STEP]
-
Step
4: Parse again...
Once you have corrected the obvious
mistakes, it's time to parse the record again. It's a good idea to
make a few corrections at a time.
By parsing every so often, you learn if the corrections you submitted
are valid and you can identify how many errors are left.
Remember,
sometimes it takes only one or two errors to cause many
Just as was it was demonstrated in Step
1, from the command prompt execute mp so that it parses the record, "jltreasure.met"
and generates an error file titled "error.txt"
by typing:
mp -e
error.txt jltreasure.met
(Command Prompt window used with mp)
MP generates the "error.txt"
file again, over-writing the earlier one. Just as
before, you need to open the "error.txt"
file (located in the c:\temp
directory) and examine the results:
(Error.txt file listing the errors after the second
parse)
** GREAT
NEWS! **
As you can see, the error listing went from 149 to 1
error and 1 bad value. This is fantastic. Now it's time
to correct the last few errors.
[RETURN TO TOP]
[NEXT STEP]
Step
5: Correcting the remaining mistakes
Just as in Step 3,
you will use Corpsmet95 to correct the last mistakes. As you found out,
the majority of the registered errors were a result of a number of
missing and/or misplaced values.
These next few mistakes are different. They are not as easily
identified and may require additional tools to
correct.
Here's what we will
do:
This concludes correcting errors.
While you can
parse the file again and receive no errors, you will continue to have
the "Upgrade" mistakes.
If you wish, you may move on to Step 6 OPTIONAL
CORRECTIONS:
These next corrections represent errors that
do not require corrections to be considered content compliant.
However, these mistakes are recommended.
Additionally, these errors also introduce an another method for error
correction.
Review the
"Upgrade" errors:
When mp indicates an "Upgrade," it usually
means that something has changed in the CSDGM
for which Corpsmet95 has
not compensated. Correcting "Upgrades" are
optional, but highly recommended.
Starting in reverse order, here is how you solve these problems
using Corpsmet95
(Corpsmet95 Create Metadata File dialog box)
Entity_and_Attribute_Information:
Detailed_Description:
Entity Type:
Entity_Type_Label: Bayou Barataria...
...
Detailed_Description:
Entity_Type:
Entity_Type_Label: Parishes...
...
Detailed_Description:
Entity_Type:
Entity_Type_Label: Raster Grid...
...
Save the changes you've made because you are
going to parse this record one last time...
[RETURN TO TOP] [NEXT
STEP]
-
Step
6: Parsing one last time...
It's finally coming to an end.
The record has been parsed, checked, and corrected twice. We shall
parse it again, just as done it Step 1 and Step
4.
(Command Prompt window used with mp)
Now that the file
"jltreasure.met" has been parsed again, we must review the
generated error.txt file for errors.
This time, as you can see, there are NO
ERRORS!!!!
Believe it or not, but you have successful metadata.
If you would like to see the corrected metadata record, you can download
and save the file:
Corrected_jltreasure.met
All that is remains to be done is generate the different file types that best
suit your needs. But don't worry about that! Why?
Because mp does it all for you, quick and easy!
But that's not until the next Lesson....
LESSON
3: Generating
Distribution Files
L
A G I C
Louisiana Geographic Information Center |
