About Amerisurv| Contact    
Magazine | Newsletter    
Flickr Photos | Advertise    
HomeNewsNewsletterAmerisurv DirectoryJobsStoreAuthorsHistoryArchivesBlogVideosEvents

Sponsored By

Software Reviews
Continuing Series
An RTN expert provides everything you need to know about network-corrected real-time GNSS observations.
Click Here to begin the series,
or view the Article PDF's Here
76-PageFlip Compilation
of the entire series
Test Yourself

Got Answers?
Test your knowledge with NCEES-level questions.
  Start HERE
Meet the Authors
Check out our fine lineup of writers. Each an expert in his or her field.
Wow Factor
Sponsored By

Product Reviews
Partner Sites







Spatial Media LLC properties




Home arrow Archives   The American Surveyor     

The HP 35s Calculator—A Field Surveyor's Companion: Part 12—Resection Print E-mail
Written by Jason E. Foose, PS   
Friday, 06 November 2015

A 227Kb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE

Most of the programming work we've experienced thus far is no more than reliable math being indisputable as to its singular solution. This multiple point Resection should offer a good solution but not an exact solution in planar geometry. Statistics tells us that there's always a better answer. I have incorporated a method that favors simplicity over the pursuit of an absolute or finite solution. The solution is derived from a series of overlapping Collin's Point Resections and the simple linear average of the aggregate x & y values of the solutions.

The Collins Method or Bessel's Method considers the occupied point and the two of three control points on a circumference. A fourth point is projected on the circumference from the occupied point through the third point. The relationship between all points is trigonometrically defined. For more information regarding resection methods and Collins Point refer to this link http://www.mesamike.org/geocache/GC1B0Q9/resection-methods.pdf

Program X and Program Y are quick utility programs that compose a complex number in and from rectangular coordinates (LBL X) and decompose a complex number in rectangular coordinates to polar coordinates (LBL Y).

I currently have all of the previously published routines along with Resection on my 35s. I am able to store points ranging from single digit point numbers to some where in the mid 400's. This is the just about the limit of practical balance between program memory and data storage allocation. Please do not hesitate to send any comments, concerns, questions, or criticism to This e-mail address is being protected from spam bots, you need JavaScript enabled to view it

Example Data and Running the Program
We will reference our previous data set as follows:


If you have carried coordinates through from the compass rule adjustment article you may find insignificant differences in solutions as noted in the May 2015 "AREA" column. The source of the error is the difference between hand entering coordinates to two decimal places versus the computed (adjusted) values that are carried out to the full 12 digit precision of the HP 35s. This is a great example toward accepting tolerance in measurement through the assessment of the source data. The amount of these differences is insignificant, however the reason they exist must be identified before considering the impact. I will be reporting will the 2 decimal coordinates listed above.

Observation Data


Observation data contains a simulated natural error of -0°00'48" to the horizon. These values will be impacted by the linear averaging of the interim solutions. Your comfort level can be ascertained by comparing raw angles to post solution values. Differences may be apparent by fixing the display to a greater precision. The solutions are accumulative therefore any inclusive interim solution should vary from any given singular solution.

The solution requires the input of adjoining (co-current) angles as delineated by "A" & "B". Note that angle 1-PNT-5 is the overlapping angle. Entry should run clockwise using angle right.


Interim/Final Solution Notes:
At this time the solution could be accepted and stored as point 10. A single three point solution may yield sufficient results. Observations can be added by repeating the steps through "MORE". Continue around the observation horizon clockwise until the "B-C" angle of the last observation is the same as the "A-B" angle of the first observation. In this case it's 49°30'20" between Points 1 & 5.


Jason Foose is the County Surveyor of Mohave County Arizona. He originally hails from The Connecticut Western Reserve Township 3, Range XIV West of Ellicott's Line Surveyed in 1785 but now resides in Township 21 North, Range 17 West of the Gila & Salt River Base Line and Meridian.

A 227Kb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE

< Prev   Next >

 American Surveyor Recent Articles
Thought Leader: Land is Too Important to Be Left to Land Specialists
A while back I was searching the Internet for an old treatise on land titles. A Google query yielded a book published in 1914. The author was Charles Claudius Kagey and the book was titled "Land Survey and Land Titles, a book for boys and girls, a reference volume for property owners, a text ....
Read the Article
Jason E. Foose, PS 
Decided Guidance: Wacker vs. Price - Irony in Sevenfold
This month's case takes us to Phoenix, Arizona in 1950. The Arizona Supreme Court went all guns-a-blazin' in Wacker vs. Price (216 P.2d 707 (Ariz. 1950)). Maybe it's just me, but I'm sensing plenty of irony and have taken license to point it out along the way. I like what the Court did with this case ....
Read the Article
Allen E. Cheves 
Around the Bend - A Visit to Carlson Software
The Ohio River is one of America's greatest, running near 1,000 miles between Pittsburgh and the Mighty Mississippi. Much of the coal and other products that fueled our nation's industrial expansion flowed between the shores of this maritime ....
Read the Article
Lee Lovell, PS 
Surveying & Mapping Economics Part 3 - Customers & Services
This article continues an inquiry into the economic conditions of the Surveying and Mapping industry (NAICS 541370) using data from the U.S. Census Bureau. This time we will look at customers and services. The data comes from the Economic Census conducted every 5 years on American ....
Read the Article
Jerry Penry, PS 
True Elevation: Black Elk Peak
Black Elk Peak, located in the Black Hills region of South Dakota, is the state's highest natural point. It is frequently referred to as the highest summit in the United States east of the Rocky Mountains. Two other peaks, Guadalupe Peak in Texas and ....
Read the Article
Larry Trojak 
Bringing The Goods - Mobile Scanning an Integral Component
When Jim Smith, Jerrad Burns and Charlie Patton left the Memphis division of a major construction company in 2015, they took with them the knowledge of how to get even the most complex jobs done and what equipment could best serve them in making that happen. So when they joined West ....
Read the Article
Lee Lovell, PS 
Test Yourself 41: Integers, Integers, and Integers
ABF is a 5:12:13 triangle, ACF is a 48:55:73 triangle, ADF is a 3:4:5 triangle, and AEF is a 7:24:25 triangle, all with integer sides and inscribed in a semi-circle. What are the lengths of BC, CD, and DE? ....
Read the Article
Wendy Lathrop, PS, CFM 
Vantage Point: Sunset or Sunrise?
While we often think of legislated government programs as static, they do change over time. Such evolution and opportunity for transformation are part of the dialogue in reauthorizing these programs. Every so many years there is a sunset on each government program, and this September is the ....
Read the Article


Amerisurv Exclusive Online-only Article ticker
Featured Amerisurv Events
List Your Event Here
contact Amerisurv


JAVAD Intros
Spoofer Buster

press [at] amerisurv.com
Online Internet Content


News Feeds

Subscribe to Amerisurv news & updates via RSS or get our Feedburn
xml feed

Need Help? See this RSS Tutorial

Historic Maps

post a job
Reach our audience of Professional land surveyors and Geo-Technology professionals with your GeoJobs career ad. Feel free to contact us if you need additional information.


Social Bookmarks

Amerisurv on Facebook 

Amerisurv LinkedIn Group 

Amerisurv Flickr Photos 

Amerisurv videos on YouTube 



The American Surveyor © All rights reserved / Privacy Statement
Spatial Media LLC
905 W 7th St #331
Frederick MD 21701
301-695-1538 - fax