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Diffstat (limited to 'Doc/library/cmath.rst')
| -rw-r--r-- | Doc/library/cmath.rst | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/Doc/library/cmath.rst b/Doc/library/cmath.rst index 83a220c..2d804c97 100644 --- a/Doc/library/cmath.rst +++ b/Doc/library/cmath.rst @@ -40,9 +40,9 @@ Definition:: In engineering the polar coordinate system is popular for complex numbers. In polar coordinates a complex number is defined by the radius *r* and the phase -angle *φ*. The radius *r* is the absolute value of the complex, which can be +angle *phi*. The radius *r* is the absolute value of the complex, which can be viewed as distance from (0, 0). The radius *r* is always 0 or a positive float. -The phase angle *φ* is the counter clockwise angle from the positive x axis, +The phase angle *phi* is the counter clockwise angle from the positive x axis, e.g. *1* has the angle *0*, *1j* has the angle *π/2* and *-1* the angle *-π*. .. note:: @@ -53,12 +53,12 @@ e.g. *1* has the angle *0*, *1j* has the angle *π/2* and *-1* the angle *-π*. Definition:: - z = r * exp(1j * φ) - z = r * cis(φ) + z = r * exp(1j * phi) + z = r * cis(phi) r := abs(z) := sqrt(real(z)**2 + imag(z)**2) phi := phase(z) := atan2(imag(z), real(z)) - cis(φ) := cos(φ) + 1j * sin(φ) + cis(phi) := cos(phi) + 1j * sin(phi) .. function:: phase(x) |