From 694370db05356b12c931a9bb4baa65a1dc0cfa16 Mon Sep 17 00:00:00 2001 From: bnewbold Date: Tue, 20 Jan 2009 22:21:06 -0500 Subject: daily, minor --- journal/19jan2009.html | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 journal/19jan2009.html (limited to 'journal/19jan2009.html') diff --git a/journal/19jan2009.html b/journal/19jan2009.html new file mode 100644 index 0000000..270f527 --- /dev/null +++ b/journal/19jan2009.html @@ -0,0 +1,50 @@ + + +bnewbold thesis + +

+Journal: Jan 19, 2009

+Bryan Newbold, bnewbold@mit.edu
+ +http://web.mit.edu/bnewbold/thesis/ +

+ + + +Finished the Seasoned Schemer yesturday. I've been looking through R5RS, it's +great how short it is! (50 pages) + +From the scmutils manual: +
+Some structures, such as the ones that represent inertia tensors, must +be inverted. (The "m" above may be an inertia tensor!) Division is +arranged to make this work, when possible. The details are too hairy +to explain in this short document. We probably need to write a book +about this! +
+Indeed! +

+I also liked this quote from Sean Carrol's Spacetime and Geometry (p485): +
+The nice property of tensors, that there is usually only one sensible thing to do based on index placement, is of great help here." +
+Sounds like a call for computation? +
+I've been working on a sage/scheme interface a bit. The problem i'm running +into now is disabling the interrupt REPL in MIT/GNU Scheme; I just want it to +leave an error string and drop back to the base REPL. I could edit the pexpect +routines in sage to try and catch all the pretinent interrupt strings, but +I think it would be better to just have the error interrupt hook in scheme +do the simple thing. +
+For now, i'm actually going to switch over to the "scm" scheme distribution +which is much simpler and get that going well with sage, then try MIT/GNU +scheme again. +

+(previous entry + + + + + -- cgit v1.2.3