How does the random reading part of the divination spell work?

The last section of the diviniation spell reads:

If you cast the spell two or more times before finishing your next long rest, there is a cumulative 25 percent chance for each casting after the first that you get a random reading. The GM makes this roll in secret.

I’m uncertain what this means, what the random reading part specifically means.

Trouble reading FITS with Mathematica 12

I’ve been using Mathematica to process FITS for years, but it has changed in version 12. Import now yields an Association rather than an Image. OK, extract item 1 from the Association, that’s an Image. But it isn’t right.

ImageData[Import["test.fits"][[1]]] 

yields a matrix full of tiny numbers like 2.81374*10^-307. This is impossible. The header has:

BITPIX = 32 / array data type

BSCALE = 1

BZERO = 2147483648

This is the conventional declaration of 32 bit unsigned integers. Apparently, these are misinterpreted as floating point.

Is this a bug, or have I missed another change?

memory usage by reading a large table in SQLite

I am new to SQLite and want to write a script that reads two columns from a table in a SQLite db file. The size of the table is 10GB. My machine has a memory of 8GB only, so reading this table entirely is impossible. If I select only two columns and read the contents, would the memory usage be 10GB and decrease, or would only the two columns be in memory after the reading operation?

Is reading from /dev/urandom on macOS Catalina a safe way to produce cryptographically secure data?

I’m reading a lot about entropy of macOS…

I know it doesn’t use Yarrow anymore but as per this FIPS 140-02 doc a NIST compliant DRBG.

I read a lot:

https://github.com/briansmith/ring/pull/398 How can I measure (and increase) entropy on Mac OS X? https://stackoverflow.com/questions/5832941/how-good-is-secrandomcopybytes http://serverascode.com/2014/03/04/yarrow.html https://stackoverflow.com/questions/3170500/random-number-generator-dev-random https://stackoverflow.com/questions/42197958/secrandomcopybytes-provider-sha1prng-or-nativeprng-type-in-objc

Even mailed Craig F: https://apple.stackexchange.com/questions/362531/does-macos-still-use-yarrow-as-its-cryptographically-secure-pseudorandom-number

I see that SecRandomCopyBytes is now effectively using:

https://opensource.apple.com/source/xnu/xnu-4570.41.2/osfmk/corecrypto/ccdbrg/src/ccdrbg_nisthmac.c.auto.html

While /dev/urandom uses:

https://opensource.apple.com/source/xnu/xnu-4570.41.2/osfmk/prng/random.c.auto.html

I have much old code using /dev/urandom, on Catalina is it still valid to use `/dev/urandom/ for key material, is it cryptographically secure?

I don’t want to port everything to a macOS specific lib.

Even libsodium seems to use /dev/random, so I guess it’s ok?

Reading in string and printing in reverse order MIPS architecture

.data string1: .space 5 str2: .asciiz “\n The output string is: ” string2: .space 5 str1: .asciiz “\n Enter the string: ” .text li $ v0, 4 la $ a0, str1 syscall

li $ v0, 8 #read in string li $ a1, 5 #the size is 4 la $ a0, string1 syscall #lw $ t7, 0($ a0) lb $ t0, 0($ a0) #1st letter lb $ t1, 1($ a0) #2nd letter lb $ t2, 2($ a0) #3rd letter lb $ t3, 3($ a0) #4th letter

addi $ sp, $ sp, -4 #allocate 4 bytes for the string sb $ t0, 0($ sp) #4th letter sb $ t1, 1($ sp) #3rd letter sb $ t2, 2($ sp) #2nd letter sb $ t3, 3($ sp) #1st letter

lb $ s0, 3($ sp) #4th letter lb $ s1, 2($ sp) #3rd letter lb $ s2, 1($ sp) #2nd letter lb $ s3, 0($ sp) #1st letter addi $ sp, $ sp, 4

sll $ s4, $ s0, 8 add $ s4, $ s4, $ s1 sll $ s4, $ s4, 8 add $ s4, $ s4, $ s2 sll $ s4, $ s4, 8 add $ s4, $ s4, $ s3

la $ t0, string2 #lw $ s4, 0($ t0)

li $ v0, 4 la $ a0, str2 syscall

li $ v0, 4 #la $ a0, string2 #prints what’s in string2 move $ a0, $ s0
syscall

li $ v0, 10 syscall

It’s giving me an error that the address is out of range. How do I print what’s in $ s4?

Accessibility – NVDA not reading text in navigation using arrow keys

am facing an issue with NVDA screen reader where in its not reading the links or text in a navigation.

Link – https://codepen.io/yogesharora28/pen/WNNPQKV

Am using arrow keys to navigate in NVDA, and if i move from a sub menu to next menu, for e.g. going from “home” and reading the items in its sub menu, moving next to “About us” menu, it wont read “About us”, instead reads the sub menu items of “about us” Any idea what could be going wrong?

What would be the purpose of a second Tarroka card reading in Curse of Strahd?

In Appendix D, the stat block of Ezmerelda d’Avenir can be found (p. 231), along with the following text:

There is also this in chapter 1 (p. 12):

Given that it is likely that the party would have found Madam Eva long before they find Ezmerelda, is this just here in case the party don’t meet Madam Eva, or is there any reason why a second card reading would be useful to them?

What would be the purpose of a second Tarroka card reading in Curse of Strahd?

In Appendix D, the stat block of Ezmerelda d’Avenir can be found (p. 231), along with the following text:

There is also this in chapter 1 (p. 12):

Given that it is likely that the party would have found Madam Eva long before they find Ezmerelda, is this just here in case the party don’t meet Madam Eva, or is there any reason why a second card reading would be useful to them?

What is google docs solution to handling multiple users editing and reading at the same time?

I have always been curious as to how google solved the solution of real time collaboration in their google docs product where they allow multiple users to edit and read the same document in real time.

I believe this is very similar to the well known readers and writers problem.

In some of the solutions that i have seen, we would need a mutex of some kind whereby the writers will have exclusive lock to the document itself and readers will not be able to read the document at all.

But in the google docs case, it is quite interesting whereby another user can read the document in real time and two users can both edit the same document at the same time without any conflicts which is very impressive to me.