TGR2SHP Read Me File

CONTENTS
1. What the program does
2. How to install
3. Program status
4. Distribution status
5. How to contact the author
6. Program execution and outputs
7. Program warnings and error messages
8. Program execution time
9. Some facts about TIGER files
10. Attributes generated by TGR2SHP


1. What the program does
	TGR2SHP is a Win95/Windows NT application for converting
TIGER 95 files to ArcView shape files.  TIGER 95 files are 
supplied by the US Census Bureau.  Descriptions of TIGER files
can be found at http://www.census.gov/geo/www/tiger. The 
program was not designed to work with earlier versions of
TIGER files.  
	Unlike most TIGER translation programs, TGR2SHP gives
you, the user, the option of choosing the features you want to 
extract.  

	The features which can be extracted are:

	Line Features: Roads, Railroads, Miscellaneous Ground 
Transport, Landmark Lines, Physical Features, Non-Visible 
Features, Hydrography, and Unknown lines.  For each line
feature, a complete from node - to node topology is created.
As a result, there are two shape files created for each line
feature type: one for the lines themselves, the other for the
corresponding node layers.

	Census Polygons: Counties, Census Tracts, Census Block 
Groups, Census Blocks, Designated Places, County Census
Divisions, Voting Districts, Indian/Alaskan Native Areas,
and Alaska Regional Native Corporation Areas.

	Other Features: Key Geographic Locations, Landmark
Polygons, Landmark Points, Traffic Analysis Zones.  In addition, 
an address file for key geographic locations is also created.

2. How to install the program
	To install this version of the program, run the program 
called limited.exe.  This is a standard windows install program.

3. Program status
	This program is a limited version of the full TGR2SHP program.
In this program, the following features are extracted:
	Rail lines and Rail nodes
	Hydrographic lines and hydrographic nodes
	Census tracts
	Key Geographic Locations

The program is shareware.

4. Distribution status
	You may distribute this demonstration version to anyone you wish.  
You may not freely distribute the full version of TGR2SHP.

5. How to contact the author
	You may contact the author, Bruce Ralston, by one of the following methods.
email: support@gistools.com
phone/fax: 423-673-8875
regular post:
Bruce Ralston
408 Kituwah Trail
Knoxville, TN 37919
USA

6. Program execution and outputs
	When the program starts, you are presented with an
initial screen.  This first screen allows you to enter the
name and location of the TIGER95 file you wish to covert to
shape files.  (Be sure you have unzipped the zip file that
comes on the TIGER CD.)  If you want to use the standard
windows File-Open dialog, click on the browse button.
	Next, click all those features you wish to extract from
TIGER and then click on the GO button.
	The second dialog screen presents an output file template 
box.  This specifies the location and name form used for the 
program outputs.  Suppose, for example, you were translating
files for Knox County, Tennessee.  Knox County's fipscode is
47093.  The default names for the program would start with
TGR47093 plus a three letter name suffix.  
The suffixes used are as follows:
	lkA for links of Type A.  Similar names are used for
links of type B, C, D, E, F, H, and X.  For roads in Knox
County, the shape file created will be named TGR47093lkA.
	ndA for nodes of Type A. Similar names are used for links
of type B, C, D, E, F, H, and X.  For roads in Knox County,
the shape file created will be named TGR47093ndA.
	cty for the County shape (e.g., TGR47093cty)
	trt for the Tract shapes 
	grp for the Block Groups
	blk for the Census Blocks
	plc for the Designated Places
	ccd for the County Census Divisions
	vot for the Voting Districts
	air for the Indian/Alaska native areas 
	arc for the Alaskan Native Regional Corporations
	kgl for the Key Geographic Locations
	lpy for the Landmark polygons
	lpt for the Landmark points
	taz for the Traffic Analysis Zones

	In addition, a dbf file containing the addresses of Key 
Geographic Locations is created.  The name suffix for that
file is add (e.g., TGR47093add.dbf).  This file can be linked to
the Key Geographic Locations shape (i.e., TGR47093kgl) in 
ArcView.

You can change the default name to whatever you would like
(for example, Knox), but the three letter suffixes will be
appended to that name.

7. Program warnings and error messages
	If a required TIGER file is missing (that is, a TIGER
file with information needed for extracting a selected
feature), an error message will be placed on the screen and
the program will terminate.  If an optional file is missing,
only a warning will be displayed.  The program will suspend
operation until you acknowledge the warning message.  This
usually occurs when you choose an option for which there are
no input files.  For example, you may choose to extract
landmark points and polygons for a county for which there are
no such entities.

8. Program execution time
	TGR2SHP is fast, much faster than other TIGER extraction
programs.  The speed of execution is dependent on the
following factors:
	1.  The size of the county.  Obviously, the larger the 
county, the longer it takes to extract its features.
	2.  The features to be extracted.  Polygons take longer
to extract than lines, and census blocks take the longest time
of all polygons.  Choosing not to extract census blocks can
cut execution time by up to 80%! 
	3.  The speed of your computer.
	4.  The amount of RAM.  The more RAM in your computer,
the faster the program.

Here are some test results for extracting TIGER features on a
Pentium Pro 200 with 64 MB of RAM.  (It is not the fastest 
computer available, so you could do much better.)  In the 
table below, the number of line features gives an idea of the 
size of the county.

County	     Number of	      Extracting 	 Without Census
Name         Line Features   All Features	    Blocks
______________________________________________________________
Loudon, TN	   8464		About 2 minutes   Under 1 min
(a small county)		
______________________________________________________________
Shelby, TN        44513		About 15 minutes  Under 4 mins 
(Home of Memphis, Elvis, etc)
______________________________________________________________
Los Angeles, CA  279754		10 hrs,22 mins	   2 hrs,20 mins
(the largest county tested)

In addition, on a 266 Pentium II machine with 64 MB of RAM,
Dade County, Florida (Miami), was converted to shape files
(including census blocks) in one hour and 12 minutes.

9. Some facts about TIGER files
	A TIGER "file" is really a set of up to 16 files.  Each
file defines a specific record type (Type 1, Type 2, up to
Type Z).  The different record types must be combined by a
translation program to build data base files usable by
commercial GIS programs.  That is, TIGER is not readily usable
by commercial GIS software.  Not all fields in a TIGER file
are populated.  For example, TIGER 95 has fields for school
districts, but they are often empty.  The same is true of the
zip code fields in the Type 1 records.  TIGER does contain
some topology (that is what the "T" in TIGER represents).
Many TIGER translators ignore this topology, and build their
own.  This is very time consuming.  TGR2SHP takes advantage
of the topology in the TIGER files.  TIGER lines have from and
to nodes locations, but not unique node numbers.  TGR2SHP
generates these node numbers for line type extracted.
	TIGER polygons correspond to feature attributes on a one-
to-one basis, a many-to-one basis, and a one-to-many basis.
An example of a one-to-one correspondence would be a census
tract polygon which corresponds to a single tract
identification (FIPS) number.  (Note: a tract, or other type
of polygon, may consist of several parts).  Many-to-one 
correspondence between polygons and features often occur
with landmark polygons.  For example, several polygons may
correspond to a river or braided stream.  Key geographic
locations can exhibit one-to-many correspondence between a
polygon and features.  For example, a polygon bounded by 
a set of roads may contain more than one shopping center.

10. Attributes generated by TGR2SHP
	The attributes generated by the program include those
which come with TIGER, and those generated by the program.

For line features:
	Those generated by the program:
		Fnode - from node id, type is numeric
		Tnode - to node id, type is numeric
		Length - length in miles, type is numeric
	Those from TIGER
		TLID - TIGER line identification. Type is 
			character
		Fedirp - Feature direction prefix (the "S" in 
			"S. Main St.")
		Fename - Feature name (the "Main" in "Main St.")
		Fetype - Feature type (the "St" in "Main St.")
		Fedirp - Feature direction suffix (the "W" in 
			"Maple Ave W")
		Cfcc  - the Census Feature Classification Code 
			(see the CFCC.csv file for definitions)
		Fraddl - the from address left
		Toaddl - the to address left
		Fraddr - the from address right
		Toaddr - the to address right
		Zipl - the Zip code on the left of the feature
		Zipr - the Zip code on the right of the feature

For the corresponding node files:
	For each line feature, a corresponding node shape is 
generated.  The only attribute associated with each node is
its ID value, which is numeric.  These ID values correspond to
the from and to node IDs in the line feature attributes.

For the census polygons:

For the County polygon
	ID - a numeric ID field, type is numeric
	Fipsstco - the county fipscode, type is character
		(note:fipscode stands for Federal Information
		Processing Standard code.)
	State - the state name, type is character
	County - the county name, type is character
For the tract polygons
	ID - a numeric ID field, type is numeric
	Tract - the tract fipscode, type is character.  The
	county fipscode is the first 5 characters of the
	tract fipscode
For the block group polygons
	ID - a numeric ID field, type is numeric
	Group - the group fipscode, type is character.  The tract
		fipscode is embedded in group fipscode
For the block polygons
	ID - a numeric ID field, type is numeric
	Block - the block fipscode, type is character.  The group
		fipscode is embedded in block fipscode
For places
	ID - a numeric ID field, type is numeric
	County - the county fipscode, type is character
	Fpl - the place fipscode, type is character
	Name - the place name, type is character
For County Census Divisions
	ID - a numeric ID field, type is numeric
	County - the county fipscode, type is character
	Fmcd - the census division fipscode, type is character
	Name - the division name, type is character
For Voting Districts
	ID - a numeric ID field, type is numeric
	County - the county fipscode, type is character
	Vote_dist - the voting district fipscode, type is
		character
	Name - the voting district name, type is character
For American Indian/Alaska Native Areas
	ID - a numeric ID field, type is numeric
	County - the county fipscode, type is character
	Air_code - the American Indian/Alaska Native Area
		fipscode, type is character
	Name - the area name, type is character
For Alaska Regional Native Corporations
	ID - a numeric ID field, type is numeric
	County - the county fipscode, type is character
	ANRC - the Alaska Regional Native Corporation fipscode,
		type is character
	Name - the area name, type is character

For other features:

For Key Geographic Locations
	ID - a numeric ID field, type is numeric
	Polyid - the Census polygon id, type is numeric
	County - the county fipscode, type is character
	Cfcc - the census feature classification code, type is
		character
	Kglname - the location name, type is character
For Landmark Polygons
	ID - a numeric ID field, type is numeric
	Polyid - the Census polygon id, type is numeric
	County - the county fipscode, type is character
	Cfcc - the census feature classification code, type is
		character
	Landname - the landmark polygon name, type is character
	Landpoly - the census landmark polygon id, type is 
		character
For Landmark Points
	ID - a numeric ID field, type is numeric
	Cfcc - the point Cfcc value, type is character
	Name - the landmark point name
For Traffic Analysis Zones
	ID - a numeric ID field, type is numeric
	County - the county fipscode, type is character
	Taz - the Traffic Analysis Zone Code, type is character
	Cttp - the Census Transportation Planning Package Area
		Code, type is character

The KGL Address database
	Some Key Geographic Locations may have addresses
associated with them.  This is particularly useful when more
than one feature is a KGL polygon.  TGR2SHP generates a
database file that contains the following information:
	Polyid - the Census polygon ID, type is numeric
	Name - the KGL name, type is character
	Address - the KGL street address, type is character
	Zipcode - the 5 digit zipcode, type is numeric
	Zip4 - the four digit zipcode suffix for zip 9 areas,
		type is numeric


