bigint

In Java 8 the below code converts integer 3 to bitset and prints {0, 1} meaning the bit representation of 3 has ones at positions 0 and 1 that is 11 . System.out.println(BitSet.valueOf(new long[]{3})); I'm interested in converting a BigInteger or long with large value, say 10000000 into the corresponding BitSet and then back - having the BitSet object (bit representation) convert it to BigInteger ( long ). I'm also wondering which representation occupies more memory for various values of integer numbers? Willem Van Onsem You can use the BigInteger.toByteArray() and BitSet.toByteArray() for

I'm trying to store in timestamp with timezone field my value. It is in milliseconds from 1970. select TO_CHAR(TO_TIMESTAMP(1401432881230), 'DD/MM/YYYY HH24:MI:SS.MS') Expected 30/5/2014 11:29:42 10:54:41.230 , but get 22/08/46379 23:27:02.000 Unix timestamps measures time with seconds, and not milliseconds ( almost everywhere, in PostgreSQL too). Therefore you need to call SELECT TO_TIMESTAMP(1401432881230 / 1000); If you want to preserve milliseconds, call with double precision : SELECT TO_TIMESTAMP(1401432881230::double precision / 1000); This is how I convert ms to timestamp and keep ms

1.bigint转成日期 SELECT from_unixtime(1496825724987/1000) 示例： starttime字段的类型是：`starttime` bigint(20) NOT NULL DEFAULT '0' COMMENT '任务的开始时间' 执行： SELECT from_unixtime(starttime/1000) FROM xxx_table; 2.日期转成bigint SELECT unix_timestamp("2018-11-20 21:44:30") * 1000 示例： `create_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '记录的创建时间' 执行： SELECT unix_timestamp(create_time) *1000 FROM `xxx_table` 来源： CSDN 作者： 一次编写 到处调试 链接： https://blog.csdn.net/u010266988/article/details/84310682

In C++, I have a bigint class that can hold an integer of arbitrary size. I'd like to convert large float or double numbers to bigint. I have a working method, but it's a bit of a hack. I used IEEE 754 number specification to get the binary sign, mantissa and exponent of the input number. Here is the code (Sign is ignored here, that's not important): float input = 77e12; bigint result; // extract sign, exponent and mantissa, // according to IEEE 754 single precision number format unsigned int *raw = reinterpret_cast<unsigned int *>(&input); unsigned int sign = *raw >> 31; unsigned int exponent

Notice For a solution in Erlang or C / C++ , go to Trial 4 below. Wikipedia Articles Integer square root The definition of "integer square root" could be found here Methods of computing square roots An algorithm that does "bit magic" could be found here [ Trial 1 : Using Library Function ] Code isqrt(N) when erlang:is_integer(N), N >= 0 -> erlang:trunc(math:sqrt(N)). Problem This implementation uses the sqrt() function from the C library, so it does not work with arbitrarily large integers (Note that the returned result does not match the input. The correct answer should be

How do one convert a big int to a string (or integer) in Golang? bigint := big.NewInt(123) //This is what I have bigstr = "123" //This is what I want Just use the String method : http://golang.org/pkg/math/big/#Int.String bigint := big.NewInt(123) bigstr := bigint.String() I used the following: bigint := big.NewInt(1231231231231) bigstr := fmt.Sprint(bigint) You asked how to convert a bigInt to string or to int, the accepted answer explains only how to convert to string. So you have your bigint := big.NewInt(123) You can convert your bigInt to integer in two possible ways: using .Int64() .

I want to change the datatype of some primary-key columns in my database from INT to BIGINT. The following definition is a toy-example to illustrate the problem: CREATE TABLE IF NOT EXISTS `owner` ( `id` int(11) NOT NULL AUTO_INCREMENT, `thing_id` int(11) NOT NULL, PRIMARY KEY (`id`), KEY `thing_id` (`thing_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ; DROP TABLE IF EXISTS `thing`; CREATE TABLE IF NOT EXISTS `thing` ( `id` int(11) NOT NULL AUTO_INCREMENT, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ;

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Am I crazy or just plain dumb? dev=# \df abuse_resolve List of functions -[ RECORD 1 ]-------+------------------------------------------------------------------------------------------------------------------------------------ Schema | public Name | abuse_resolve Result data type | record Argument data types | INOUT __abuse_id bigint, OUT __msg character varying Type | normal dev=# select abuse_resolve('30'::bigint); ERROR: function abuse_resolve(bigint) does not exist LINE 1: select abuse_resolve('30'::bigint); ^ HINT: No function matches