Rod – absolute gold putting these all together, Looking for the HP35 programs which died with the batteries I googled and found the answer right here on your site. Instead of searching through my dusty Survey notes I can come here and have the answers at my fingertips. The notes on Horizontal curves have refreshed my memory and provided assistance in a tunneling issue we have up at Craigieburn for Yarra Valley Water. Thanks for your efforts in collating all these notes. Regards
Hi Rod,
Thank you for putting all your notes together like this.
I’ve ended up in the geodetic section at the OSGV where I’ve called upon your notes more than once.
There’s no doubt that I’ll need to again in the future.
Regards
This paper was very important in my understanding of the various lines, and provided a baseline for my software implementations. I did have one issue that I was unable to resolve, however. In table 9, longitude E. My software gives 445.9767 rather than 4599767 for the distance from the normal section. Am I in error or is this errata in your paper? Thanks.
Dear Charles,
You sent me a comment on 30-Jun-2021 relating to a paper on the website http://www.mygeodesy.id.au Thank you very much for locating an error in my calculations. I’m assuming that the paper you were referring to was the one about The Black-Allan Line and I checked some of the relevant computations and found that I couldn’t multiply two numbers! You are indeed correct, the distance (along the meridian) from the normal section to the loxodrome is 445.9767 m (and not 459.9767 m as shown in the paper). It could also have been a typo. I’m afraid a lot of my work relied on me as the ‘checker’.
Hi Rod,
I’ve been diving into catenaries, and I found your paper to be super helpful. But I’m trying to derive the length from a known sag (d in your paper), and I’m struggling. Is it possible to solve for the ‘a’ parameter using only d, v, and h instead of L, v, and h (your equation 37)? I do understand how to solve for ‘a’ numerically afterwards, but I just can’t figure out the right equation. Any help would be appreciated!
Hi Rod,
Just shared a meal with Ron and Wendy Grenfell.
Ron alerted me to your great website.
Years ago at a surveying/cartography camp you penned for me the mathematics behind a sundial.
Is this something you could add to your website?
Cheers,
Hi Rod, I’m a surveyor and excel enthusiast. I’m referring to your paper on the Freenet Adjustment for a level network published in 2006. Very interesting, but, there is an error in the Matrix N on Page 4. N11 is shown as w1+w2+w3 on page 3. but this value is really 2.025 and not 1.5 which is likely w1+w4+w5. Using the value of 2.025 simply doesnt work for a solution. N is not singular if you use 2.025. Also, I ran the numbers without weights and I got a slightly better solution in terms of the norm of X and the residuals were generally smaller.
Truly a stupendous effort. I hope that all this effort is not lost.
I am very grateful that you offered me the chance to see your work.
Rod – absolute gold putting these all together, Looking for the HP35 programs which died with the batteries I googled and found the answer right here on your site. Instead of searching through my dusty Survey notes I can come here and have the answers at my fingertips. The notes on Horizontal curves have refreshed my memory and provided assistance in a tunneling issue we have up at Craigieburn for Yarra Valley Water. Thanks for your efforts in collating all these notes. Regards
Dear Chris,
Thanks for your kind words.
Rod Deakin (randm.deakin@gmail.com)
Hi Rod,
Thank you for putting all your notes together like this.
I’ve ended up in the geodetic section at the OSGV where I’ve called upon your notes more than once.
There’s no doubt that I’ll need to again in the future.
Regards
Hello. Thanks a lot! Great article.
thnx for sharing your well put together web page.
You have got among the best internet websites.
Hi there. Thanks a lot! Excellent article.
This paper was very important in my understanding of the various lines, and provided a baseline for my software implementations. I did have one issue that I was unable to resolve, however. In table 9, longitude E. My software gives 445.9767 rather than 4599767 for the distance from the normal section. Am I in error or is this errata in your paper? Thanks.
Dear Charles,
You sent me a comment on 30-Jun-2021 relating to a paper on the website http://www.mygeodesy.id.au Thank you very much for locating an error in my calculations. I’m assuming that the paper you were referring to was the one about The Black-Allan Line and I checked some of the relevant computations and found that I couldn’t multiply two numbers! You are indeed correct, the distance (along the meridian) from the normal section to the loxodrome is 445.9767 m (and not 459.9767 m as shown in the paper). It could also have been a typo. I’m afraid a lot of my work relied on me as the ‘checker’.
Regards
Rod Deakin (randm.deakin@gmail.com)
07-Jul-2021
Hi Rod,
I’ve been diving into catenaries, and I found your paper to be super helpful. But I’m trying to derive the length from a known sag (d in your paper), and I’m struggling. Is it possible to solve for the ‘a’ parameter using only d, v, and h instead of L, v, and h (your equation 37)? I do understand how to solve for ‘a’ numerically afterwards, but I just can’t figure out the right equation. Any help would be appreciated!
Hi Rod,
Just shared a meal with Ron and Wendy Grenfell.
Ron alerted me to your great website.
Years ago at a surveying/cartography camp you penned for me the mathematics behind a sundial.
Is this something you could add to your website?
Cheers,
Hi Rod, I’m a surveyor and excel enthusiast. I’m referring to your paper on the Freenet Adjustment for a level network published in 2006. Very interesting, but, there is an error in the Matrix N on Page 4. N11 is shown as w1+w2+w3 on page 3. but this value is really 2.025 and not 1.5 which is likely w1+w4+w5. Using the value of 2.025 simply doesnt work for a solution. N is not singular if you use 2.025. Also, I ran the numbers without weights and I got a slightly better solution in terms of the norm of X and the residuals were generally smaller.
Andrew