What does 'j' stand for in python?

Question

Why abs(3 + 4j) equals 5.0? What does 'j' mean?

Answer 1

j equals to sqrt(-1) -- and, like Pulkit already mentioned, relates to iota in mathematics, it is the imaginary part of the complex numbers.
abs() measures the distance between the argument and the number 0. The distance is by definition always positive. Whenever you deal with complex numbers you have at least one of the coordinates as imaginary. And so in your equation you measure the distance from 0 to 3 (which is 3) and the distance between 0 and 4j (which is 4). This happens to be the classical Pythagorean triangle with 3, 4 and 5 as sides, just one of them is on the imaginary dimension. So the sum of squares: 3² + 4² equals to 5².

Answer 2

j stands for complex part of a complex number in python, it is same as iota(i) in maths.
the magnitude of 3+4j=√(3**2+4**2)=5(abs is magnitude of a complex number in maths)
for more details, refer chapter complex numbers in maths.

Answer 3

Its the magnitude or "length" of the complex number, (3+4j) where j is the imaginary unit. j, the imaginary unit is the square root of -1. The solution of the equation x^2 + 1 = 0. An Imaginary number is a real number times the imaginary unit. Complex numbers have both a real part and an imaginary part. Real numbers fill a number line, 1 dimensional, but complex numbers cover a 2 dimensional plane (complex plane). When plotting a complex number, the real part is on the x-axis and the imaginary part is plotted at right angle to the real part (the y-axis). the magnitude of a complex number is the length of the radius vector from the origin to the point in the complex plane representing the complex number. Given a complex number, a+bj, the magnitude is sqrt(a**2 + b**2), if R =a and I = bj then the magnitude is
sqrt(R**2 - I**2)
In this particular case (3 + 4j) we have two sides of a 3, 4, 5 right triangle, so the magnitude is 5.

Answer 4

Thx, I got it now :)

Answer 5

j stands early to responds to JavaScript frameworks JavaScript simple and easy language for people in research and quest

Answer 6

It indicates that is imaginary part of your complex number it's same as i (iota) in maths.

Answer 7

for that you can just say that 2*9j=2*9*√(-1)=18√-1=18j
as j=√-1

Answer 8

un numero complejo es de la forma : a+bj , donde a,b son reales y j**2 = -1, j se le llama la unidad imaginaria.
podemos sumar complejos así: (2+3j) + (5-4j)= (2+5)+(3-4)j, es decir sumamos partes reales y partes imaginaria.
podemos multiplicar complejos así : 2*(3+j)=2*3+2*j=6+2*j es similar a la ley distributiva.

Answer 9

Thank you!