What's the difference between directrix and eccentricity?

Directrix


Definition:

  • (n.) A directress.
  • (n.) A line along which a point in another line moves, or which in any way governs the motion of the point and determines the position of the curve generated by it; the line along which the generatrix moves in generating a surface.
  • (n.) A straight line so situated with respect to a conic section that the distance of any point of the curve from it has a constant ratio to the distance of the same point from the focus.

Example Sentences:

Eccentricity


Definition:

  • (n.) The state of being eccentric; deviation from the customary line of conduct; oddity.
  • (n.) The ratio of the distance between the center and the focus of an ellipse or hyperbola to its semi-transverse axis.
  • (n.) The ratio of the distance of the center of the orbit of a heavenly body from the center of the body round which it revolves to the semi-transverse axis of the orbit.
  • (n.) The distance of the center of figure of a body, as of an eccentric, from an axis about which it turns; the throw.

Example Sentences:

  • (1) Periosteal chondroma is an uncommon benign cartilagenous lesion, and its importance lies primarily in its characteristic radiographic and pathologic appearance which should be of assistance in the differential diagnosis of eccentric lesions of bones.
  • (2) Adaptation at 10 deg eccentricity yielded slightly higher threshold elevations than for central vision.
  • (3) An in vitro, eccentric arterial stenosis model was created using 15 canine carotid arteries cannulated with silicone plugs containing special pressure-transducing catheters designed to measure pressure directly, within the stenosis.
  • (4) • Gaddafi's many eccentricities, including phobias about flying over water and staying above ground floor level.
  • (5) These data suggest that older adults experience greater muscle damage following eccentric exercise than young subjects, which may be due in part to the smaller muscle mass and lower VO2max seen in older men.
  • (6) Detection thresholds at 10 Hz and high grating contrasts were approximately 11-15 arcsec in the fovea and 37-47 arcsec at 30 degrees eccentricity.
  • (7) It could be said that Brown's methods were not eccentric but merely attuned to the demands of Eighties and Nineties culture.
  • (8) That detail is inspired by the eccentric Mancunian performer Frank Sidebottom – the film is co-written by the Guardian's Jon Ronson , a former member of Sidebottom's band – but Abrahamson insists the character stands in for all music's outsiders.
  • (9) The relationships between dioptric blur, pupil size, retinal eccentricity, and retinal sensitivity were investigated in the central 5 degrees of the visual field in 10 normal subjects using the Humphrey Field Analyzer.
  • (10) Some say Film Socialism is an eccentric masterpiece ; others that it's an eccentric mess.
  • (11) The neoplastic cells have large, single eccentric nucleus, resembling typical plasma cells.
  • (12) Our threshold vs ISI data can be adequately modeled on the basis of an intrinsic positional uncertainty, which increases with eccentricity, and additive and multiplicative sources of noise.
  • (13) The latter 7 cases had either a dislocation or an eccentration.
  • (14) The term Asperger's Syndrome (AS) refers to a clinical picture characterized by social isolation in combination with odd and eccentric behaviour.
  • (15) With calcium antagonists, a similar extent of dilation of normal coronary arteries and eccentric stenoses can be obtained.
  • (16) The size and the angular tilt of the dark crescent appearing in the subject's pupil are derived as a function of five variables: the ametropia of the eye (Dsph, Dcyl, axis), the eccentricity of the flash, e, and the distance of the camera from the subject's eye, dc.
  • (17) Eccentric catheter location had little effect on phantom or human arterial lumen shape or area when imaging was performed with optimized catheters.
  • (18) Accommodative microfluctuations were found to play a minor role in determining the magnitude of sensitivity out to an eccentricity of 5 degrees; between 5 degrees and 27.5 degrees, the effect of microfluctuations was masked by the mydriasis produced by the drugs used in the study.
  • (19) A sport-specific profile of eccentric and concentric enlargement has been documented in endurance and resistance athletes, respectively.
  • (20) Although containing no obviously extreme items, its cumulative effect may be used to assess the prevalence of bizarre and eccentric thought patterns in psychiatric patients, and as an estimate of psychotic risk in the general population.