Scientific Computation

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Scientific Computation

• Whats the big idea?

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A scientific toolbox

• A computer is a general-purpose tool for
  processing information
• Main goal of CS112 is to learn how to build your
  own specialized tools for scientific work
• Your tools will be computer programs written in
  MATLAB

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Data visualization and analysis

• Graphical display of data
• Statistical analysis of data
• Fitting functions to data

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Sunspots

• Discovered independently by Christoph Scheiner
  (1610) and Galileo (1613)
• Indicate disturbances in the suns magnetic field
• The number of sunspots varies over time in a
  cyclical way
• Sunspot Cycle discovered by Samuel Schwabe
  (1843)

There is some connection between sunspots and
extreme weather
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The sunspot data
How can we determine the length of the sunspot
cycle?
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The length of the sunspot cycle 12 years
Note virtually no sunspot activity in the years
1650-1700 (Europes mini ice-age) and were
currently in a low spot in the cycle!
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Visualizing data
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Whodunit?
9
Create synthetic data and images
simultaneous contrast illusion

• Perceptual experiments collect data from human
  subjects, analyze data, implement and test models
  of human visual processing

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Ribonucleic acid

• An RNA molecule is a sequence of nucleotides
  drawn from Adenine (A), Guanine (G), Cytosine
  (C), and
• Uracil (U)
• Three adjacent nucleotides form a triplet called
  a codon that corresponds to a single amino acid
• Youll write a MATLAB program that translates a
  sequence of RNA nucleotides to an amino-acid
  sequence

UANCUAUCUAUCUUCCGGUC ... ? Tyr Leu Ser Ile Phe
Gln Val ....
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Searching databases

• What is the average cholesterol level for women
  in their twenties who exercise at least 30
  minutes a day?

cholesterol
...
189
239
178
185
251
165
age
...
25
35
28
40
28
22
sex
...
m
m
f
m
m
f
exercise
...
30
15
40
25
15
60
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Designing GUIs

• Graphical User Interfaces simplify communication
  with our programs by using text boxes, pop-up
  windows, buttons, menus, check boxes, sliders,
  etc.
• Well use MATLABs GUI facilities to build our
  own interactive programs

Pronounced gooey
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Physical simulation

• Prof. Yue Hu in Physics, together with students
  Nicole DuRand 06 and Christina Miller 08,
  created animations in MATLAB that simulate simple
  physical systems
• The MathWorks website has many more examples

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Credits
Plotting emissions test data
http//www.mathworks.com/demos/matlab/...
analyzing-data-overview-matlab-video-demonstr
ation.html Sunspot data and image
http//www.macalester.edu/kaplan
http//web.me.com/uriarte/Earths_Climate/...
Sunspots_and_solar_cycles_files/sunspot032
901.gif Visualization examples
http//scv.bu.edu/SCV/vizgal
http//visualizationlab.vassar.edu/instvishome
MATLAB Help Visualizing MRI data
http//www.mathworks.com/products/matlab/demos.htm
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