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Absolute value of a complex number

We denote the set of complex numbers by C. Readers should be familiar with complex numbers and how to add and multiply them, as described in many standard calculus texts. We use i to denote the square root of —1 and an asterisk to denote complex conjugation if x and y are real numbers, then (x + iy) = X — iy. Later in the text, we will use the asterisk to denote the conjugate transpose of a matrix with complex entries. This is perfectly consistent if one thinks of a complex number x + iy as a one-by-one complex matrix ( x + iy ). See also Exercise 1.6. The absolute value of a complex number, also known as the modulus, is denoted... [Pg.21]

As we have seen, if is a root of a polynomial equation, then z is also a root. Recall that for real numbers, absolute value refers to the magnitude of a number, independent of its sign. Thus, 3.14 = — 3.14 = 3.14. We can also write - 3.14 = - 3.14. The absolute value of a complex number z, also called its magnitude or modulus, is likewise written as z - It is defined by... [Pg.44]

Modulus ma-j3-l3s -li [NL, fr. L, small measure] (1753) n, pi. (1) A modulus is a measure of a mechanical property of a material, most frequently a stiffness property. (2) The absolute value of a complex number or quantity, equal to the square root of the sum of the squares of the real and imaginary parts. (3) Modulus at 300% n The tensile stress required to elongate a specimen to three times its original length (200% elongation) divided by 2. Although other elongations are used, 300% is the one most often employed for rubbers and flexible plastics. [Pg.627]

Particle physics, however, works with complex quantities of the form x = a + ib, where i is the imaginary unit, i = — 1. The measurable physical quantities are always real, so they contain the absolute values of the complex numbers,... [Pg.460]

In the case of C resonances, the common standard is the molecule tetramethyl silane (TMS, Si(CH3)4 ) and its frequency as measured in the liquid or low pressure gas at room temperature, is taken as corresponding to an isotropic chemical shift of zero. In the case of the theoretical calculations the absolute values of a are calculated, and the C isotropic shift (trace of the chemical shieding tensor) corresponding to an isolated TMS molecule derived from the Pulay program is 186 ppm. This, as well as some of the more recent programs, has been extensively used to calculate the chemical shifts or magnetic susceptibilities of a large number of nuclei in isolated molecules and only recently applied to nuclei in zeolites and the adsorption complex. [Pg.168]

The angle 9, called the phase angle, simply describes the rotation of z in the complex plane. The square of the absolute value can be shown to be identical to the product of z = x + iy and its complex conjugate z =x — iy. The complex conjugate of a complex number is formed by changing the sign of the imaginary part. [Pg.9]

We use common (but not universal) mathematical notation and terminology for functions. When we define a function, we indicate its domain (the objects it can accept as arguments), the target space (the kind of objects it puts out as values) and a rule for calculating the value from the argument. For example, if we wish to introduce a function f that takes a complex number to its absolute value squared, we write... [Pg.18]

In Table VII are recorded mean values for in a number of ethylene-metal carbonyl complexes and parent metal carbonyls as well as values for the double-bond infrared stretching frequency rc c the magnetic shielding parameter t for ethylene in those transition metal complexes for which data are available. Although with the metal carbonyl complexes, differences of geometry, oxidation state, etc., do not permit a correlation to be drawn between the absolute values of rco and for the various complexes, it is quite apparent from the tabulated data for the Mo, Mn, and Fe complexes that for a given metal. [Pg.351]

F is, in general, a complex number, and it expresses both the amplitude and phase of the resultant wave. Its absolute value i gives the amplitude of the resultant wave in terms of the amplitude of the wave scattered by a single electron. Like the atomic scattering factor/, Ifj is defined as a ratio of amplitudes ... [Pg.120]

The amplitude is a complex number, whose absolute value has the dimension of a length. In the limit k0 -> 0, this number becomes real. It is called the collision length. [Pg.193]

If Fhid is known for a large number of hkl reflections, (1.98) can be inverted to obtain pu(r) and hence the positions of all the atoms in the unit cell. Such an endeavor is called the crystal structure analysis and is explained in more detail in Section 3.3. The intensity of reflection, observed at s = r%kl is equal to F/ / 2. The absolute value of Fhki can therefore be obtained as the square root of the observed intensity of the hkl reflection, but the intensity data do not provide any direct information about the phase angle of the complex Fw A major task in crystal structure analysis is solving the phase problem to determine the phases of the structure factors. [Pg.33]

F. Consequently, the scattering amplitude, e, is a complex number whose amplitude reflects the scattering strength, and whose phase factor determines the constructive and destructive interference conditions for any particular value of Q. The diffraction intensities are proportional to the magnitude of the scattering amplitudes. Consequently the intensities do not depend upon an absolute phase, but instead on the relative phases for each scattering event. [Pg.155]

Balancing of an oxidation-reduction reaction is a little more complex than balancing a simple reaction. The main rule that you have to follow when balancing oxidation-reduction reactions is that the absolute value of the increase in oxidation number of all the atoms that are oxidized should equal the absolute value of the decrease in oxidation number of all the atoms that are reduced. Balancing oxidation-reduction reaction is sometimes time-consuming and quite often frustrating. We will look at two methods of balancing oxidation-reduction reactions. [Pg.28]

Note that only the absolute value of B has been determined. B could be —(2//) as well as 2/1 1. Moreover, B need not be a real number. We could use any complex number with absolute value (2//). All we can say is that B = (2//) e , where a is the phase of B and could be any value in the range 0 to 27t (Section 1.7). Choosing the phase to be zero, we write as the stationary-state wave functions for the particle in a box... [Pg.26]

A complex number is an ordered pair of real numbers, for instance G and B. Introducing the imaginary unit j = the complex number Y = G + jB. G is the real part and can be written Y, and B the imaginary part written Y". Y or Y is called the absolute value, magnitude, or modulus, and the phase angle is cp = arctan B/G. [Pg.506]

According to HALIM et al. (2008), some steps can be evaluated in order to calculate the TDAS if x(n) represents the vibration signals on time domain, and the number of wavelet scales r is S, then the wavelet transformation of x(n) would generate the wavelet coefficient W(s, n), which is a matrix of SxN dimension. The matrix W (s, n) may be a complex matrix depending on the wavelet used. By taking the absolute value of each of the elements of the matrix W(s, n), the matrix V(s,n) is produced, where all elements of V (s, n) are real. Each row of this matrix is a time series corresponding to one scale s with period P. Recall that the period of the time series is P and the time series has exactly M periods, so that N = P x M. Each of these time series can be synchronously averaged based on... [Pg.196]


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See also in sourсe #XX -- [ Pg.47 ]

See also in sourсe #XX -- [ Pg.47 ]

See also in sourсe #XX -- [ Pg.30 ]




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