Meaning of (Number) & (-Number)

meaning of (number) & (-number)

Assuming 2's complement (or that i is unsigned), -i is equal to ~i+1.

i & (~i + 1) is a trick to extract the lowest set bit of i.

It works because what +1 actually does is to set the lowest clear bit, and clear all bits lower than that. So the only bit that is set in both i and ~i+1 is the lowest set bit from i (that is, the lowest clear bit in ~i). The bits lower than that are clear in ~i+1, and the bits higher than that are non-equal between i and ~i.

Using it in a loop seems odd unless the loop body modifies i, because i = i & (-i) is an idempotent operation: doing it twice gives the same result again.

[Edit: in a comment elsewhere you point out that the code is actually i += i & (-i). So what that does for non-zero i is to clear the lowest group of set bits of i, and set the next clear bit above that, for example 101100 -> 110000. For i with no clear bit higher than the lowest set bit (including i = 0), it sets i to 0. So if it weren't for the fact that i starts at 0, each loop would increase i by at least twice as much as the previous loop, sometimes more, until eventually it exceeds n and breaks or goes to 0 and loops forever.

It would normally be inexcusable to write code like this without a comment, but depending on the domain of the problem maybe this is an "obvious" sequence of values to loop over.]

Kaggle Dataset - Letter and numbers meaning

The number 0.00256 is expressed as 2.56E-03 in scientific notation .

What this means is that the number before E (2.56 in this case) is multiplied by 10 raised to the power of -3 , which is 2.56*10^(-3) .

Similarly the number 744.67 is expressed as 7.4467E+02.

For example , your first y value (1.975000E-01) would be 0.1975 since it is 1.975 * 10^(-1) .

Your first x value (4.0E+00) would simply be 4 since it is 4.0*10^(0).

What is the meaning of number 1e5?

1e5 is a number expressed using scientific notation and it means 1 multiplied by 10 to the 5th power (the e meaning 'exponent')

so 1e5 equals 1*100000and is equal to 100000, the three notations are interchangeable meaning the same.

Does anyone here know what (if number % 2 == 1) does?

The % operator calculates the modulus (integer remainder); number % 2 gives you the remainder of number divided by 2:

The % (modulo) operator yields the remainder from the division of the first argument by the second.

It basically tests if the number is odd (which gives you a remainder of 1), skipping to the next iteration of the loop if it is.

What is the meaning of exclusive and inclusive when describing number ranges?

The following function prints the powers of 2 from 1 through n (inclusive).

This means that the function will compute 2^i where i = 1, 2, ..., n, in other words, i can have values from 1 up to and including the value n. i.e n is Included in Inclusive

If, on the other hand, your book had said:

The following function prints the powers of 2 from 1 through n (exclusive).

This would mean that i = 1, 2, ..., n-1, i.e. i can take values up to n-1, but not including, n, which means i = n-1 is the highest value it could have.i.e n is excluded in exclusive.

What is the meaning of numbers in inline assemble

Those are local labels (numbers followed by a colon).

When they are later referenced, the b (as in jmp 1b) means to refer to the nearest local label of that number going backwards. An f would look for a matching local label later (forwards) in the code.

That code declares an exception table, when an exception occurs executing the wrmsr instruction, the fault handler (usually in arch/<your_CPU_arch>/mm/fault.c) searches the exception table for the corresponding entry, and jumps there.

As you can see, the entry for that exception moves EIO into err, and jumps back to the instruction following the xor (which would clear err in case there was no error).

What's the meaning of typeof Array[number] in Typescript?

typeof gets the type of names variable (which is readonly ['jacob', 'master jung', 'kyuhyun']) then array/tuple member type is resolved. This is called indexed access types or lookup types.

Syntactically, they look exactly like an element access, but are written as types

In this case we "query" the type of tuple member (tuple/array at index) which is 'jacob' | 'master jung' | 'kyuhyun'

Playground

could someone explain what is the meaning of (number % 10); , (number % 100)/10; and so-on?

The % sign is the Quotient.

So in your example:
The number is = 12345

so number % 1000;

is basically 12345 divide to 1000 which is 12 and 345/1000,

Now the % action will result with the remains Quotient which is 345,

Later you divided it by 100 which result with 3.45,

When you will use something li Math.floor() you will end with number 3

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