Science and Sensitivity Science

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Science and SensitivityScience
ComputersPHY307/PHY607Sept. 24, 2002
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Exams, projects

• Midterm is Oct. 22. types of problems
• Project proposal is due Oct. 10.
• Will skip quizzes.

Homework

• Fireworks.

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Homework

• Fireworks.

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from mymodule import from random import
scene.autoscale 0 sparks for i in
range(100) sparks.append(sphere(radius0.2))
  for s in sparks s.vel vector(random()-0.5,
random()-0.5,random()-0.5)
s.vel s.vel/mag(s.vel) grav
vector(0,-0.1,0) dt 0.05 while 1
rate(20) for s in sparks for each
sphere, fall(s, grav, dt) have sphere
fall
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Arrays, lists, vectors

• Lists can be of any type, but dont support math.
• Arrays are usually numbers and do support math
  operations on the elements.
• Vectors are arrays of length 3 (like x,y,z
  coordinates.)

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Arrays, lists, vectors sample

• a arange(0,5,1)
• l range(5)
• v vector(0,1,2)
• print a
• print l
• print v
• print a a
• print a a
• print a / 2.
• print l l
• print l l
• print v v
• print v v

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Loops

• for loops
• Repeats actions (block statement)
• For each item in a list
• while loops
• Repeats actions while some condition is true
  (not zero.)
• A condition is an expression, likea lt 10 a is
  less than 10b 3 b is equal to 3a lt 10 and
  b 3 both conditions holda gt 10 or a lt 5 one
  of the conditions hold1 true0 false

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while examples

• a0
• while a lt 10
• print a
• aa3

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while examples

• from visual import
• a box()
• while a.x lt 10 and a.y lt 64
• rate(5)
• a.x a.x 0.5
• a.y a.y 10

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Problems with for

• from visual import
• sphlist
• for j in range(0,20,4)
• sphlist.append(sphere(xj))
• for s in sphlist
• s sphere()
• s.color color.red

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if else examples

• a 3.9
• x 0.26
• for j in range(20)
• x a x (1.-x)
• if x gt 0.8
• print x is larger than 0.8 at step, j