random

How to implement a function of a random variable in PyMC which could be sampled by MCMC Metropolis?

由 早过忘川 提交于 2020-01-06 15:04:50
问题 If you have a random variable $X$ and a function $f$, you can define $y=f(X)$ as a new random variable with a probability density function as follows: $p(y)=(f^{-1})'(y)p(x)$. For details see here. Now I have defined a random variable alpha, with an exponential distribution in the following code. I want to add to my model, log(alpha) as a new random variable. How should I implement it in my model? I already made an effort but it seems that it is wrong, and the reason as been pointed out in

How to implement a function of a random variable in PyMC which could be sampled by MCMC Metropolis?

由 一笑奈何 提交于 2020-01-06 15:03:41
问题 If you have a random variable $X$ and a function $f$, you can define $y=f(X)$ as a new random variable with a probability density function as follows: $p(y)=(f^{-1})'(y)p(x)$. For details see here. Now I have defined a random variable alpha, with an exponential distribution in the following code. I want to add to my model, log(alpha) as a new random variable. How should I implement it in my model? I already made an effort but it seems that it is wrong, and the reason as been pointed out in

How to assign a function in Lua for a randomly generated numbers

由 北城余情 提交于 2020-01-06 14:19:38
问题 First I stored 10 images in array(i.e., table) from 1-10 as key values and I create a random number using math.random function between 0-9., and I need to access the image that is stored in array by the value created by random function, and assign the touch function for the particular image file alone., Ex: If the random function creates number as "5" I need to move the image 5.png that is stored in array index as 5 .,other images except 5.png should not use touch function., (i.e., they are

How to assign a function in Lua for a randomly generated numbers

由 半腔热情 提交于 2020-01-06 14:19:27
问题 First I stored 10 images in array(i.e., table) from 1-10 as key values and I create a random number using math.random function between 0-9., and I need to access the image that is stored in array by the value created by random function, and assign the touch function for the particular image file alone., Ex: If the random function creates number as "5" I need to move the image 5.png that is stored in array index as 5 .,other images except 5.png should not use touch function., (i.e., they are

How to generate unique random numbers in an array

由 泄露秘密 提交于 2020-01-06 13:03:51
问题 I'm having trouble with this assignment that requires me to create 50 random unique numbers without using ArrayLists. I'm required to use a boolean array that checks whether the random number has already been generated. Each number that is generated out of 50 will be set to true in the boolean array. Ex. Generating a number 23 would make check[23]=true. The problem I am having is an error in the while loop that keeps on generating a new random number even if there is no other unique number

How to generate unique random numbers in an array

由 本小妞迷上赌 提交于 2020-01-06 12:58:30
问题 I'm having trouble with this assignment that requires me to create 50 random unique numbers without using ArrayLists. I'm required to use a boolean array that checks whether the random number has already been generated. Each number that is generated out of 50 will be set to true in the boolean array. Ex. Generating a number 23 would make check[23]=true. The problem I am having is an error in the while loop that keeps on generating a new random number even if there is no other unique number

7.6 passwd：修改用户密码

由 笑着哭i 提交于 2020-01-06 09:59:10
7.6 passwd：修改用户密码 passwd命令可以修改用户密码及密码过期时间等内容，是工作中很常用的命令。普通用户和超级用户都可以运行passwd命令，但普通用户只能更改自身的用户密码，超级用户root则可以设置或修改所有用户的密码。 -k 为密码已经过期的用户更新有效期 -l 锁定用户，被锁定的用户将不能登录。仅root用户有权使用该选项 -stdin 从标准输入读取密码字符串深 -u 解除对用户的锁定。仅root用户有权使用该选项 -d 删除用户的密码，使密码为空。仅root用户有权使用该选项 -e 使用户密码立即过期，将在用户下次登录时强制要求用户修改密码。仅root用户有权使用该选项 -n 设置修改密码的最短天数。仅root用户有权使用该选项 -x 设置修改密码的最长天数。仅root用户有权使用该选项 -w 设置用户在密码过期前收到警告信息的天数。仅root用户有权使用该选项 -i 设置密码过期多少天后禁用账户。仅root用户有权使用该选项 -S 显示用户密码相关的简单描述。仅root用户有权使用该选项 除了上述说明，还要强调以下两点。 root用户可以修改任何用户的密码，普通用户只能修改自身的密码。 root用户修改密码时，如果不符合系统密码规则，则给出警告信息，但密码设置仍然生效。普通用户修改密码时，如果使用弱密码，则给出告警信息，且修改无效。 修改用户密码的例子

The relationship between bits and int/float random number generator

由 混江龙づ霸主 提交于 2020-01-06 08:30:45
问题 I want to figure out the relationship between bits and RNG for int or float. (By random I mean uniformly distributed) I am given a perfect boolean random generator, and I am asked to implement a random 32 bits integer generator (including negative, zero and positive). What I want to do is generate a random boolean for each of the 32 bits, and concat them together to be a random int . Am I doing the right thing? Also from the other way around, if I am given a perfect random 32 bits integer

rand() seeded the same way generates different results

由 放肆的年华 提交于 2020-01-06 08:01:31
问题 I am developing an application in PHP and C but the result of rand is different between the two languages, even though I am using the same seed: PHP: srand(1); $random = rand(); // returns 32422 C: srand(1); int random = rand(); // returns 41 Why is this happening? 回答1: There is more than one way to implement a pseudo-random number generator. Every programming language is free to specify its own rand implementation, or even to specify nothing. For example, the C specification only says that

rand() seeded the same way generates different results

由 允我心安 提交于 2020-01-06 08:01:02
问题 I am developing an application in PHP and C but the result of rand is different between the two languages, even though I am using the same seed: PHP: srand(1); $random = rand(); // returns 32422 C: srand(1); int random = rand(); // returns 41 Why is this happening? 回答1: There is more than one way to implement a pseudo-random number generator. Every programming language is free to specify its own rand implementation, or even to specify nothing. For example, the C specification only says that
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