Hi there, I am running code that calculates some Max Likeihood values by solving some equations using Newton-Raphson method. In this case **any** value between (and including) 0 and 1 is possible. I do this for a large number of parameters in a long running loop. Every so often I write this out to an SQLite database.
Going through the SQLite code, while the database reads are "binary" the inserts are by submitting a SQL command of the form - 'insert into MLE (psi, var, p, s, k) values ' , Followed by a formatted list of lists of values (0.7, 0.1, 0.7, 3, 7), (0.3, 0.2, 0.5, 3, 8), ... The SQLite routines need to get the formatted values. Foreign verb 8!:0 is used to format up character representations. Verb sqlinsert_psqlite_ calls fixcol which uses the 8!:0 foreign verb. I now discover that some of my calculations end up extremely small (< 1e_300), and these produce a system error in 8!:0. The code below demonstrates the problem. JVERSION Engine: j805/j64/windows Beta-12: commercial/2016-09-30T15:50:47 Library: 8.05.14 Qt IDE: 1.5.3/5.6.2 Platform: Win 64 Installer: J805 install InstallPath: r:/j/j64-805 Contact: www.jsoftware.com 8!:0 ] 9.06184e_293 3.71249e_297 3.66555e_301 7.57543e_305 2.9368e_308 1.95799e_311 jtsprintfeD: decpt |system error | 8!:0]9.06184e_293 3.71249e_297 3.66555e_301 7.57543e_305 |2.9368e_308 1.95799e_311 [[[Note underscores are sometimes screwed by this email system]]] Issues: A/ Can 8!:0 check for positive numbers less than 10e_310 (and negative numbers greater than _10e_310) B/ Is it possible for SQLite insert verbs to use binary transfer instead of formatting up an sql insert command. C/ Is it the case that foreign 8!:0 actually uses a J coded verb jtsprintfeD and/or decpt? D/ Why won't email editor correctly handle underscores? Sometime underscores appear correctly other times they are invisible? Ian Ian Shannon Science Strategy Branch Science Division Office of Environment and Heritage PO Box A290 Sydney South NSW 1232 T: +61 2 99 955 490 E: Ian Determinant Shannon Atop Environment Determinant nsw Determinant gov Determinant au Please consider the environment before printing my email A recent survey has found that 6 out of 7 people includes approximately 86% of the population ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- This email is intended for the addressee(s) named and may contain confidential and/or privileged information. If you are not the intended recipient, please notify the sender and then delete it immediately. Any views expressed in this email are those of the individual sender except where the sender expressly and with authority states them to be the views of the NSW Office of Environment and Heritage. PLEASE CONSIDER THE ENVIRONMENT BEFORE PRINTING THIS EMAIL ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
